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  • CLASSES

    Fluoroquinolone Antibiotics
    Ophthalmological Anti-infectives

    BOXED WARNING

    Corticosteroid therapy, organ transplant, tendinitis, tendinopathy, tendon pain, tendon rupture

    Systemic quinolones have been associated with disabling and potentially irreversible serious adverse reactions such as tendinopathy, including tendinitis and tendon rupture requiring surgical repair or resulting in prolonged disability. These reactions can occur within hours to weeks after starting these agents in patients of any age, with or without pre-existing risk factors. Because of this risk for serious and potentially permanent side effects, quinolones should only be used for the treatment of uncomplicated urinary tract infection, acute bacterial exacerbation of chronic bronchitis, or acute bacterial sinusitis in cases where alternative treatment options cannot be used. Discontinue quinolones at the first sign of tendon inflammation or tendon pain as these are symptoms that may precede rupture of the tendon. Avoid quinolone use in patients with a history of tendon disorders or tendon rupture. Tendon rupture typically involves the Achilles tendon; however, ruptures of the hand, shoulder, biceps, thumb, and other tendons have also been reported. Tendinitis and tendon rupture can occur bilaterally. Rupture can occur during therapy or up to a few months after therapy has been stopped. The risk of tendon rupture is increased in older adults over 60 years of age, those receiving concomitant corticosteroid therapy, and in organ transplant recipients (including kidney, heart, and lung transplants). Other reasons for tendon ruptures include physical activity or exercise, kidney failure, or tendon problems in the past. If patients experience tendon inflammation or pain, they should rest and refrain from exercise until the diagnosis of tendonitis or tendon rupture has been confidently excluded.

    Arteriosclerosis, cerebrovascular disease, depression, neurotoxicity, peripheral neuropathy, psychiatric event, seizure disorder

    Systemic quinolones have been associated with disabling and potentially irreversible serious neurotoxicity, including central nervous system effects, peripheral neuropathy, or psychiatric event. These reactions can occur within hours to weeks after starting these agents in patients of any age, with or without pre-existing risk factors. Because of this risk for serious and potentially permanent side effects, use quinolones for the treatment of uncomplicated urinary tract infection, acute bacterial exacerbation of chronic bronchitis, or acute bacterial sinusitis only in cases where alternative treatment options cannot be used. Avoid quinolone use in patients who have previously experienced peripheral neuropathy. Additionally, use quinolones with caution in patients with a known or suspected CNS disorder (e.g., severe cerebrovascular disease or arteriosclerosis, seizure disorder) or in the presence of other risk factors (e.g., certain drug therapy, renal dysfunction) that may predispose to seizures or lower seizure threshold. Attempted or completed suicide has been reported, especially in patients with a history of depression, or an underlying risk factor for depression. Discontinue quinolone therapy at the first signs or symptoms of neuropathy (e.g., pain, burning, tingling, numbness, and/or weakness, or other alterations in sensations such as light touch, pain, temperature, position sense, and vibratory sensation, and/or motor strength), central nervous system adverse events (seizures or convulsions, increased intracranial pressure (including pseudotumor cerebri), dizziness, or tremors), or psychiatric adverse events (toxic psychosis, hallucinations, paranoia, depression, suicidal thoughts or acts, confusion, delirium, disorientation, disturbances in attention, anxiety, agitation, nervousness, insomnia, nightmares, or memory impairment).

    Myasthenia gravis

    Avoid use of systemic quinolones, such as levofloxacin, in patients with a history of myasthenia gravis. Systemic quinolones may exacerbate the signs of myasthenia gravis and lead to life threatening weakness of the respiratory muscles. Serious postmarketing events, including deaths and the requirement for ventilatory support, have been associated with quinolone use in patients with myasthenia gravis. Because of this risk for serious and potentially permanent side effects, quinolones should only be used for the treatment of uncomplicated urinary tract infection, acute bacterial exacerbation of chronic bronchitis, or acute bacterial sinusitis in cases where alternative treatment options cannot be used.

    DEA CLASS

    Rx

    DESCRIPTION

    Oral, ophthalmic, and IV quinolone antibiotic
    Used for bacterial conjunctivitis, sinusitis, chronic bronchitis, pneumonia, skin and skin structure infections, UTIs, prostatitis, inhalation anthrax, and plague
    Associated with disabling and potentially irreversible adverse reactions, including tendonitis, tendon rupture, peripheral neuropathy, and central nervous system effects

    COMMON BRAND NAMES

    Iquix, Levaquin, Levaquin Leva-Pak, Quixin

    HOW SUPPLIED

    Iquix/Levofloxacin/Quixin Ophthalmic Sol: 0.5%, 1.5%
    Levaquin/Levaquin Leva-Pak/Levofloxacin Oral Tab: 250mg, 500mg, 750mg
    Levaquin/Levofloxacin Oral Sol: 1mL, 25mg
    Levaquin/Levofloxacin/Levofloxacin, Dextrose Intravenous Inj Sol: 1mL, 25mg, 5-5%

    DOSAGE & INDICATIONS

    For the treatment of acute bacterial sinusitis.
    Oral dosage
    Adults

    500 mg PO once daily for 5 to 10 days as alternative therapy in patients with beta-lactam allergy or risks for resistance, those requiring hospitalization, or patients who failed initial therapy. The FDA-approved dose is 500 mg PO every 24 hours for 10 to 14 days or 750 mg PO every 24 hours for 5 days. Due to the risk for serious and potentially permanent side effects associated with quinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    Infants†, Children†, and Adolescents†

    10 to 20 mg/kg/day PO divided every 12 to 24 hours (Max: 500 mg/day) for 10 to 14 days as alternative therapy in patients with beta-lactam allergy or risks for resistance, those requiring hospitalization, or patients who failed initial therapy. Due to the risk for serious and potentially permanent adverse reactions associated with quinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    Intravenous dosage
    Adults

    500 mg IV once daily for 5 to 10 days as alternative therapy in patients with beta-lactam allergy or risks for resistance, those requiring hospitalization, or patients who failed initial therapy.  The FDA-approved dose is 500 mg IV every 24 hours for 10 to 14 days or 750 mg IV every 24 hours for 5 days. Due to the risk for serious and potentially permanent side effects associated with quinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    Infants†, Children†, and Adolescents†

    10 to 20 mg/kg/day IV divided every 12 to 24 hours (Max: 500 mg/day) for 10 to 14 days as alternative therapy in patients with beta-lactam allergy or risks for resistance, those requiring hospitalization, or patients who failed initial therapy. Due to the risk for serious and potentially permanent adverse reactions associated with quinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    For the treatment of urinary tract infection (UTI), including cystitis and pyelonephritis.
    For treatment of complicated UTI, including acute pyelonephritis.
    Oral dosage
    Adults

    750 mg PO every 24 hours for 5 days or 250 mg PO every 24 hours for 10 days. Guidelines suggest the 5-day regimen for patients with acute pyelonephritis not requiring hospitalization and for catheter-associated UTI.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours for 5 days or 250 mg IV every 24 hours for 10 days.

    For treatment of uncomplicated UTI, including cystitis.
    Oral dosage
    Adults

    250 mg PO every 24 hours for 3 days. Due to the risk for serious and potentially permanent side effects associated with fluoroquinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    Intravenous dosage
    Adults

    250 mg IV every 24 hours for 3 days. Due to the risk for serious and potentially permanent side effects associated with fluoroquinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    For treatment of uncomplicated UTI, including cystitis, due to resistant gram-negative organisms.
    Oral dosage
    Adults

    750 mg PO every 24 hours for 3 days. Due to the risk for serious and potentially permanent side effects associated with fluoroquinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours for 3 days. Due to the risk for serious and potentially permanent side effects associated with fluoroquinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    For treatment of complicated UTI, including acute pyelonephritis due to resistant gram-negative organisms.
    Oral dosage
    Adults

    750 mg PO every 24 hours for 5 days. Clinical practice guidelines suggest the 5-day regimen for patients with acute pyelonephritis not requiring hospitalization and for catheter-associated UTI.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours for 5 days.

    For the treatment of acute bacterial exacerbations of chronic bronchitis.
    Oral dosage
    Adults

    500 mg PO every 24 hours for 5 to 7 days. Due to the risk for serious and potentially permanent side effects associated with fluoroquinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    Intravenous dosage
    Adults

    500 mg IV every 24 hours for 5 to 7 days. Due to the risk for serious and potentially permanent side effects associated with fluoroquinolone antibiotics, levofloxacin should only be used in cases where alternative treatment options cannot be used.

    For the treatment of community-acquired pneumonia (CAP) and nosocomial pneumonia.
    For the treatment of nosocomial pneumonia, including infections due to resistant gram-negative organisms.
    Oral dosage
    Adults

    750 mg PO every 24 hours for 7 days as a singular agent or as part of combination therapy.[61215] The FDA-approved duration is 7 to 14 days.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours for 7 days as a singular agent or as part of combination therapy.[61215] The FDA-approved duration is 7 to 14 days.

    For the treatment of community-acquired pneumonia (CAP), including infections due to resistant gram-negative organisms.
    Oral dosage
    Adults

    750 mg PO every 24 hours for at least 5 days.[34362] [64669] Alternatively, 500 mg PO every 24 hours for 7 to 14 days. Guidelines recommend levofloxacin as monotherapy for outpatients with comorbidities or hospitalized patients with nonsevere pneumonia and as part of combination therapy for hospitalized patients with severe pneumonia. Guide treatment duration by clinical stability.[34362] [64669]

    Adolescents†

    8 to 10 mg/kg/dose (Max: 750 mg/dose) PO every 24 hours for 5 to 10 days.[34362] [46963] Guidelines recommend levofloxacin as an alternative empiric therapy for hospitalized patients with presumed bacterial or atypical pneumonia, as preferred oral step-down therapy for patients with penicillin-resistant S. pneumoniae, and as alternative oral step-down therapy for patients with penicillin-susceptible S. pneumoniae, M. pneumoniae, or C. trachomatis, or C. pneumoniae.[46963] For persons living with HIV, levofloxacin is recommended as monotherapy for outpatients or hospitalized patients with nonsevere pneumonia or as part of combination therapy for hospitalized patients with severe pneumonia.[34362]

    Children 5 to 12 years†

    8 to 10 mg/kg/dose (Max: 750 mg/dose) PO every 24 hours for 10 days. Guidelines recommend levofloxacin as an alternative empiric therapy for hospitalized patients with presumed bacterial or atypical pneumonia, as preferred oral step-down therapy for patients with penicillin-resistant S. pneumoniae, and as alternative oral step-down therapy for patients with penicillin-susceptible S. pneumoniae, M. pneumoniae, or C. trachomatis, or C. pneumoniae.[46963]

    Infants and Children 6 months to 4 years†

    8 to 10 mg/kg/dose PO every 12 hours for 10 days. Guidelines recommend levofloxacin as an alternative empiric therapy for hospitalized patients with presumed bacterial or atypical pneumonia, as preferred oral step-down therapy for patients with penicillin-resistant S. pneumoniae, and as alternative oral step-down therapy for patients with penicillin-susceptible S. pneumoniae, M. pneumoniae, or C. trachomatis, or C. pneumoniae.[46963]

    Intravenous dosage
    Adults

    750 mg IV every 24 hours for at least 5 days.[34362] [64669] Alternatively, 500 mg IV every 24 hours for 7 to 14 days. Guidelines recommend levofloxacin as monotherapy for hospitalized patients with nonsevere pneumonia or as part of combination therapy for hospitalized patients with severe pneumonia. Guide treatment duration by clinical stability.[34362] [64669]

    Adolescents†

    8 to 10 mg/kg/dose (Max: 750 mg/dose) IV every 24 hours for 5 to 10 days.[34362] [46963] Guidelines recommend levofloxacin as an alternative empiric therapy for hospitalized patients with presumed bacterial or atypical pneumonia and as an alternative for patients with penicillin-resistant S. pneumoniae, H. influenzae, M. pneumoniae, C. trachomatis, or C. pneumoniae.[46963] For persons living with HIV, levofloxacin is recommended as monotherapy for hospitalized patients with nonsevere pneumonia or as part of combination therapy for hospitalized patients with severe pneumonia.[34362]

    Children 5 to 12 years†

    8 to 10 mg/kg/dose (Max: 750 mg/dose) IV every 24 hours for 10 days. Guidelines recommend levofloxacin as an alternative empiric therapy for hospitalized patients with presumed bacterial or atypical pneumonia and as an alternative for patients with penicillin-resistant S. pneumoniae, H. influenzae, M. pneumoniae, C. trachomatis, or C. pneumoniae.[46963]

    Infants and Children 6 months to 4 years†

    8 to 10 mg/kg/dose IV every 12 hours for 10 days. Guidelines recommend levofloxacin as an alternative empiric therapy for hospitalized patients with presumed bacterial or atypical pneumonia and as an alternative for patients with penicillin-resistant S. pneumoniae, H. influenzae, M. pneumoniae, C. trachomatis, or C. pneumoniae.[46963]

    For the treatment of skin and skin structure infections, including impetigo, cellulitis, skin abscesses, furunculosis, pyoderma, animal bite wounds, diabetic foot ulcer, and surgical incision site infections.
    For the treatment of diabetic foot ulcer.
    Oral dosage
    Adults

    750 mg PO every 24 hours for 7 to 14 days for mild infections in patients allergic or intolerant to beta-lactams or with recent antibiotic exposure or for moderate or severe infections in patients with risk factors for resistant gram-negative infections. Consider adding clindamycin for moderate or severe infections. Continue treatment for up to 28 days if infection is improving but is extensive and resolving slower than expected or if patient has severe peripheral artery disease.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours for 7 to 14 days for mild infections in patients allergic or intolerant to beta-lactams or with recent antibiotic exposure or for moderate or severe infections in patients with risk factors for resistant gram-negative infections. Consider adding clindamycin for moderate or severe infections. Continue treatment for up to 28 days if infection is improving but is extensive and resolving slower than expected or if patient has severe peripheral artery disease.

    For the treatment of surgical incision site infections.
    Oral dosage
    Adults

    750 mg PO every 24 hours plus metronidazole for incisional surgical site infections of the axilla or perineum.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours plus metronidazole for incisional surgical site infections of the intestinal or genitourinary tract or axilla or perineum.

    For the treatment of animal bite wounds.
    Oral dosage
    Adults

    750 mg PO every 24 hours plus an anaerobic agent. In setting of a cat or dog bite, preemptive early antimicrobial therapy for 3 to 5 days is recommended for patients who are immunocompromised, asplenic, have advanced liver disease, have edema of the bite area, have moderate to severe injuries, particularly of the hand or face, or have penetrating injuries to the periosteum or joint capsule.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours plus an anaerobic agent. In setting of a cat or dog bite, preemptive early antimicrobial therapy for 3 to 5 days is recommended for patients who are immunocompromised, asplenic, have advanced liver disease, have edema of the bite area, have moderate to severe injuries, particularly of the hand or face, or have penetrating injuries to the periosteum or joint capsule.

    For the treatment of unspecified uncomplicated skin and skin structure infections.
    Oral dosage
    Adults

    500 mg PO every 24 hours for 7 to 10 days.

    Intravenous dosage
    Adults

    500 mg IV every 24 hours for 7 to 10 days.

    For the treatment of unspecified complicated skin and skin structure infections, including infections due to resistant gram-negative organisms.
    Oral dosage
    Adults

    750 mg PO every 24 hours for 7 to 14 days.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours for 7 to 14 days.

    For the treatment of bacterial conjunctivitis.
    Ophthalmic dosage
    Adults

    1 to 2 drops in affected eye(s) every 2 hours while awake, up to 8 times per day on days 1 and 2. On days 3 through 7, 1 to 2 drops every 4 hours while awake, up to 4 times per day.

    Children and Adolescents

    1 to 2 drops in affected eye(s) every 2 hours while awake, up to 8 times per day on days 1 and 2. On days 3 through 7, 1 to 2 drops every 4 hours while awake, up to 4 times per day.

    For anthrax prophylaxis after exposure to Bacillus anthracis (postexposure prophylaxis, PEP).
    Oral dosage
    Adults

    750 mg PO every 24 hours for 60 days after exposure. Alternately, FDA-approved labeling suggests 500 mg PO every 24 hours. Safety beyond 28 days has not been studied in the adult population. Levofloxacin is recommended as an alternative therapy for postexposure prophylaxis. Preferred therapies are ciprofloxacin or doxycycline.

    Children and Adolescents weighing 50 kg or more

    500 mg PO every 24 hours for 60 days after exposure; however, safety beyond 14 days has not been studied in the pediatric population. Levofloxacin is recommended as an alternative therapy for postexposure prophylaxis. Preferred therapies are ciprofloxacin or doxycycline.

    Infants 6 to 11 months, Children, and Adolescents weighing less than 50 kg

    8 mg/kg/dose PO every 12 hours (Max: 250 mg/dose) for 60 days after exposure; however, safety beyond 14 days has not been studied in the pediatric population. Levofloxacin is recommended as an alternative therapy for postexposure prophylaxis. Preferred therapies are ciprofloxacin or doxycycline.

    Infants 1 to 5 months†

    8 mg/kg/dose PO every 12 hours for 60 days after exposure; however, safety beyond 14 days has not been studied in the pediatric population. Levofloxacin is recommended as an alternative therapy for postexposure prophylaxis. Preferred therapies are ciprofloxacin or doxycycline.

    Intravenous dosage
    Adults

    500 mg IV every 24 hours for 60 days after exposure. Clinical practice guidelines do not address IV prophylaxis; the recommended oral prophylaxis dose is 750 mg. Safety beyond 28 days has not been studied in the adult population. Levofloxacin is recommended as an alternative therapy for postexposure prophylaxis. Preferred therapies are ciprofloxacin or doxycycline.

    Children and Adolescents weighing 50 kg or more

    500 mg IV every 24 hours for 60 days after exposure; however, safety beyond 14 days has not been studied in the pediatric population. Levofloxacin is recommended as an alternative therapy for postexposure prophylaxis. Preferred therapies are ciprofloxacin or doxycycline.

    Infants 6 to 11 months, Children, and Adolescents weighing less than 50 kg

    8 mg/kg/dose IV every 12 hours (Max: 250 mg/dose) for 60 days after exposure; however, safety beyond 14 days has not been studied in the pediatric population. Levofloxacin is recommended as an alternative therapy for postexposure prophylaxis. Preferred therapies are ciprofloxacin or doxycycline.

    Infants 1 to 5 months†

    8 mg/kg/dose IV every 12 hours for 60 days after exposure; however, safety beyond 14 days has not been studied in the pediatric population. Levofloxacin is recommended as an alternative therapy for postexposure prophylaxis. Preferred therapies are ciprofloxacin or doxycycline. Although the clinical practice guidelines only give oral dosing recommendations for agents for postexposure prophylaxis, the IV levofloxacin dosage is the same as the oral dosage and may be used for patients unable to take PO.

    For the treatment of plague infection.
    For the treatment of bubonic or pharyngeal plague.
    Oral dosage
    Adults

    750 mg PO every 24 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment of naturally occurring plague in pregnant patients and patients infected after intentional release of Y. pestis. The FDA-approved dosage is 500 mg to 750 mg PO every 24 hours.

    Children and Adolescents weighing 50 kg or more

    500 to 750 mg PO every 24 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    Children and Adolescents weighing less than 50 kg

    8 mg/kg/dose (Max: 250 mg/dose) PO every 12 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    Infants 6 to 11 months

    8 mg/kg/dose PO every 12 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    Infants 1 to 5 months†

    8 mg/kg/dose PO every 12 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    Neonates†

    10 mg/kg/dose PO every 12 hours or 10 to 14 days as first-line therapy. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment of naturally occurring plague in pregnant patients and patients infected after intentional release of Y. pestis. The FDA-approved dosage is 500 mg to 750 mg IV every 24 hours.

    Children and Adolescents weighing 50 kg or more

    500 to 750 mg IV every 24 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    Children and Adolescents weighing less than 50 kg

    8 mg/kg/dose (Max: 250 mg/dose) IV every 12 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    Infants 6 to 11 months

    8 mg/kg/dose IV every 12 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    Infants 1 to 5 months†

    8 mg/kg/dose IV every 12 hours for 10 to 14 days as first-line therapy. Monotherapy is recommended for stable patients with naturally occurring plague, although dual therapy can be considered for patients with large buboes. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    Neonates†

    10 mg/kg/dose IV every 12 hours for 10 to 14 days as first-line therapy. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients infected after intentional release of Y. pestis.

    For the treatment of pneumonic or septicemic plague.
    Oral dosage
    Adults

    750 mg PO every 24 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment of naturally occurring plague in pregnant patients, patients with severe disease, and patients infected after intentional release of Y. pestis. The FDA-approved dosage is 500 mg to 750 mg PO every 24 hours.

    Children and Adolescents weighing 50 kg or more

    500 to 750 mg PO every 24 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    Children and Adolescents weighing less than 50 kg

    8 mg/kg/dose (Max: 250 mg/dose) PO every 12 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    Infants 6 to 11 months

    8 mg/kg/dose PO every 12 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    Infants 1 to 5 months†

    8 mg/kg/dose PO every 12 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    Neonates†

    10 mg/kg/dose PO every 12 hours for 10 to 14 days as first-line therapy. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment of naturally occurring plague in pregnant patients, patients with severe disease, and patients infected after intentional release of Y. pestis. The FDA-approved dosage is 500 mg to 750 mg IV every 24 hours.

    Children and Adolescents weighing 50 kg or more

    500 to 750 mg IV every 24 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    Children and Adolescents weighing less than 50 kg

    8 mg/kg/dose (Max: 250 mg/dose) IV every 12 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    Infants 6 to 11 months

    8 mg/kg/dose IV every 12 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    Infants 1 to 5 months†

    8 mg/kg/dose IV every 12 hours for 10 to 14 days as first-line therapy. Monotherapy can be considered for mild-to-moderate disease in patients with naturally occurring plague. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    Neonates†

    10 mg/kg/dose IV every 12 hours for 10 to 14 days as first-line therapy. Use dual therapy with 2 distinct classes of antimicrobials for initial treatment in patients with severe disease and patients infected after intentional release of Y. pestis.

    For the treatment of plague meningitis†.
    Oral dosage
    Adults

    750 mg PO every 24 hours in combination with chloramphenicol for 10 to 14 days. If chloramphenicol is not available, a nonfluoroquinolone first-line or alternative antimicrobial for treatment of septicemic plague can be substituted. For patients with secondary plague meningitis, add levofloxacin to the existing antimicrobial regimen and continue the entire regimen for an additional 10 days.

    Children and Adolescents weighing 50 kg or more

    500 to 750 mg PO every 24 hours in combination with chloramphenicol for 10 to 14 days. If chloramphenicol is not available, a nonfluoroquinolone first-line or alternative antimicrobial for treatment of septicemic plague can be substituted. For patients with secondary plague meningitis, add levofloxacin to the existing antimicrobial regimen and continue the entire regimen for an additional 10 days.

    Infants, Children, and Adolescents weighing less than 50 kg

    8 mg/kg/dose (Max: 250 mg/dose) PO every 12 hours in combination with chloramphenicol for 10 to 14 days. If chloramphenicol is not available or not desired due to potential toxicity in young children, a nonfluoroquinolone first-line or alternative antimicrobial for treatment of septicemic plague can be substituted. For patients with secondary plague meningitis, add levofloxacin to the existing antimicrobial regimen and continue the entire regimen for an additional 10 days.

    Neonates

    10 mg/kg/dose PO every 12 hours in combination with chloramphenicol for 10 to 14 days. If chloramphenicol is not available or not desired due to potential toxicity in young children, a nonfluoroquinolone first-line or alternative antimicrobial for treatment of septicemic plague can be substituted. For patients with secondary plague meningitis, add levofloxacin to the existing antimicrobial regimen and continue the entire regimen for an additional 10 days.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours in combination with chloramphenicol for 10 to 14 days. If chloramphenicol is not available, a nonfluoroquinolone first-line or alternative antimicrobial for treatment of septicemic plague can be substituted. For patients with secondary plague meningitis, add levofloxacin to the existing antimicrobial regimen and continue the entire regimen for an additional 10 days.

    Children and Adolescents weighing 50 kg or more

    500 to 750 mg IV every 24 hours in combination with chloramphenicol for 10 to 14 days. If chloramphenicol is not available, a nonfluoroquinolone first-line or alternative antimicrobial for treatment of septicemic plague can be substituted. For patients with secondary plague meningitis, add levofloxacin to the existing antimicrobial regimen and continue the entire regimen for an additional 10 days.

    Infants, Children, and Adolescents weighing less than 50 kg

    8 mg/kg/dose (Max: 250 mg/dose) IV every 12 hours in combination with chloramphenicol for 10 to 14 days. If chloramphenicol is not available or not desired due to potential toxicity in young children, a nonfluoroquinolone first-line or alternative antimicrobial for treatment of septicemic plague can be substituted. For patients with secondary plague meningitis, add levofloxacin to the existing antimicrobial regimen and continue the entire regimen for an additional 10 days.

    Neonates

    10 mg/kg/dose IV every 12 hours in combination with chloramphenicol for 10 to 14 days. If chloramphenicol is not available or not desired due to potential toxicity in young children, a nonfluoroquinolone first-line or alternative antimicrobial for treatment of septicemic plague can be substituted. For patients with secondary plague meningitis, add levofloxacin to the existing antimicrobial regimen and continue the entire regimen for an additional 10 days.

    For plague prophylaxis.
    For pre-exposure prophylaxis†.
    Oral dosage
    Adults

    500 to 750 mg PO every 24 hours until 48 hours after the last perceived exposure as first-line therapy.

    Pregnant patients

    750 mg PO every 24 hours until 48 hours after the last perceived exposure as first-line therapy.

    Children and Adolescents weighing 50 kg or more

    500 to 750 mg PO every 24 hours until 48 hours after the last perceived exposure as first-line therapy.

    Infants, Children, and Adolescents weighing less than 50 kg

    8 mg/kg/dose (Max: 250 mg/dose) PO every 12 hours until 48 hours after the last perceived exposure as first-line therapy.

    For postexposure prophylaxis.
    Oral dosage
    Adults

    500 to 750 mg PO every 24 hours for 7 days as first-line therapy. The FDA-approved duration is 10 to 14 days.

    Pregnant patients

    750 mg PO every 24 hours for 7 days as first-line therapy. The FDA-approved dosage is 500 mg PO every 24 hours for 10 to 14 days.

    Children and Adolescents weighing 50 kg or more

    500 to 750 mg PO every 24 hours for 7 days as first-line therapy. The FDA-approved duration is 10 to 14 days.

    Children and Adolescents weighing less than 50 kg

    8 mg/kg/dose (Max: 250 mg/dose) PO every 12 hours for 7 days as first-line therapy. The FDA-approved duration is 10 to 14 days.

    Infants 6 to 11 months

    8 mg/kg/dose PO every 12 hours for 7 days as first-line therapy. The FDA-approved duration is 10 to 14 days.

    Infants 1 to 5 months†

    8 mg/kg/dose PO every 12 hours for 7 days as first-line therapy.

    Neonates†

    10 mg/kg/dose PO every 12 hours for 7 days as first-line therapy.

    Intravenous dosage
    Adults

    500 to 750 mg IV every 24 hours for 7 days as first-line therapy. The FDA-approved duration is 10 to 14 days.

    Pregnant patients

    750 mg IV every 24 hours for 7 days as first-line therapy. The FDA-approved dosage is 500 mg IV every 24 hours for 10 to 14 days.

    Children and Adolescents weighing 50 kg or more

    500 to 750 mg IV every 24 hours for 7 days as first-line therapy. The FDA-approved duration is 10 to 14 days.

    Children and Adolescents weighing less than 50 kg

    8 mg/kg/dose (Max: 250 mg/dose) IV every 12 hours for 7 days as first-line therapy. The FDA-approved duration is 10 to 14 days.

    Infants 6 to 11 months

    8 mg/kg/dose IV every 12 hours for 7 days as first-line therapy. The FDA-approved duration is 10 to 14 days.

    Infants 1 to 5 months†

    8 mg/kg/dose IV every 12 hours for 7 days as first-line therapy.

    Neonates†

    10 mg/kg/dose IV every 12 hours for 7 days as first-line therapy.

    For the treatment of drug-susceptible tuberculosis infection† as part of combination therapy.
    Oral dosage
    Adults

    500 to 1,000 mg PO once daily or 5 days/week.[34362] [61094] Daily dosing is defined as 5- or 7 days/week.[61094] [65619] Levofloxacin is generally recommended as second-line therapy; duration is dependent on the site of involvement.[61094] [65619]

    Infants, Children, and Adolescents

    15 to 20 mg/kg/dose (Max: 1,000 mg/dose) PO once daily or 5 days/week. Daily dosing is defined as 5- or 7 days/week. Levofloxacin is generally recommended as second-line therapy; duration is dependent on the site of involvement.

    Intravenous dosage
    Adults

    500 to 1,000 mg IV once daily or 5 days/week. Daily dosing is defined as 5- or 7 days/week.  Levofloxacin is generally recommended as second-line therapy; duration is dependent on the site of involvement.

    Infants, Children, and Adolescents

    15 to 20 mg/kg/dose (Max: 1,000 mg/dose) IV once daily or 5 days/week. Daily dosing is defined as 5- or 7 days/week. Levofloxacin is generally recommended as second-line therapy; duration is dependent on the site of involvement.

    For the treatment of Mycobacterium avium complex infection† (MAC) in HIV-infected patients.
    Oral dosage
    Adults

    500 mg PO once daily plus clarithromycin or azithromycin and ethambutol. May consider addition of levofloxacin as a third or fourth drug (or rifabutin, amikacin, streptomycin, or moxifloxacin) for patients with high mycobacterial loads (more than 2 log CFU/mL of blood) or in the absence of effective antiretroviral therapy. Duration of treatment depends on clinical response but should continue for at least 12 months.[34362]

    Adolescents

    500 mg PO once daily plus clarithromycin or azithromycin and ethambutol. May consider addition of levofloxacin as a third or fourth drug (or rifabutin, amikacin, streptomycin, or moxifloxacin) for patients with high mycobacterial loads (more than 2 log CFU/mL of blood) or in the absence of effective antiretroviral therapy. Duration of treatment depends on clinical response but should continue for at least 12 months.[34362]

    Children

    500 mg PO once daily in children who are old enough to receive adult dosing plus clarithromycin or azithromycin and ethambutol.[34361] Doses of 15 to 20 mg/kg/day PO divided every 12 hours have been used in children (weighing less than 50 kg) for other indications.[57108] [61095] May consider addition of levofloxacin if rifabutin cannot be administered for severe disease or if a fourth drug is needed for patients with more severe symptoms or disseminated disease. Duration of treatment depends on clinical response but should continue for at least 12 months.[34361]

    For the treatment of chlamydia infection†.
    Oral dosage
    Adults

    500 mg PO every 24 hours for 7 days as an alternative.

    Children and Adolescents weighing 45 kg or more

    500 mg PO every 24 hours for 7 days an alternative.

    For the treatment of chronic bacterial prostatitis or epididymitis†.
    For the treatment of epididymitis†.
    Oral dosage
    Adults

    500 mg PO once daily for 10 days for enteric organisms; add ceftriaxone IM if likely due gonorrhea, chlamydia, or enteric organisms.

    Children weighing 45 kg or more and Adolescents

    500 mg PO once daily for 10 days for enteric organisms; add ceftriaxone IM if likely due gonorrhea, chlamydia, or enteric organisms.

    For the treatment of chronic bacterial prostatitis.
    Oral dosage
    Adults

    500 mg PO once daily for 28 days.

    Intravenous dosage
    Adults

    500 mg IV once daily for 28 days.

    For the treatment of pelvic inflammatory disease (PID)†.
    Oral dosage
    Adults

    Due to resistance, guidelines no longer recommend the use of quinolones. However, if allergy precludes the use of parenteral cephalosporin therapy, levofloxacin 500 mg PO daily plus metronidazole for 14 days may be considered if the community prevalence and individual risk for gonorrhea are low. Diagnostic testing for gonorrhea must be performed before starting therapy.

    Adolescents

    Due to resistance, guidelines no longer recommend the use of quinolones. However, if allergy precludes the use of parenteral cephalosporin therapy, levofloxacin 500 mg PO daily plus metronidazole for 14 days may be considered if the community prevalence and individual risk for gonorrhea are low. Diagnostic testing for gonorrhea must be performed before starting therapy.

    For Helicobacter pylori (H. pylori) eradication†.
    As part of initial therapy.
    Oral dosage
    Adults

    250 or 500 mg PO once daily as part of combination therapy as a first-line treatment option. Triple therapy includes levofloxacin 500 mg PO once daily in combination with amoxicillin and a proton pump inhibitor (PPI) for 10 to 14 days. Sequential therapy may begin after 5 to 7 days of amoxicillin and a PPI as levofloxacin 500 mg PO once daily in combination with a nitroimidazole and a PPI for 5 to 7 days. Quadruple therapy includes levofloxacin 250 mg PO once daily in combination with nitazoxanide, doxycycline, and a PPI for 7 to 10 days.

    As part of salvage therapy.
    Oral dosage
    Adults

    500 mg PO once daily in combination with amoxicillin and a proton pump inhibitor (PPI) for 14 days. Guidelines recommend this triple therapy in patients who have failed clarithromycin-triple or bismuth-quadruple initial therapies and without previous quinolone exposure. Levofloxacin in combination with metronidazole and a PPI for 14 days could be considered for patients with a penicillin allergy who have failed prior bismuth quadruple therapy.

    For the treatment of salmonellosis† in HIV-infected patients.
    Oral dosage
    Adults

    750 mg PO every 24 hours is recommended by the CDC as alternative therapy. The duration of therapy is 7 to 14 days for patients with CD4 count of 200 cells/mm3 or more without bacteremia, 14 days for patients with CD4 count of 200 cells/mm3 or more and bacteremia, and 2 to 6 weeks for patients with CD4 count less than 200 cells/mm3. Consider secondary prophylaxis for patients with recurrent bacteremia or recurrent gastroenteritis with or without bacteremia when CD4 count less than 200 cells/mm3 with severe diarrhea.

    Adolescents

    750 mg PO every 24 hours is recommended by the CDC as alternative therapy. The duration of therapy is 7 to 14 days for patients with CD4 count of 200 cells/mm3 or more without bacteremia, 14 days for patients with CD4 count of 200 cells/mm3 or more and bacteremia, and 2 to 6 weeks for patients with CD4 count less than 200 cells/mm3. Consider secondary prophylaxis for patients with recurrent bacteremia or recurrent gastroenteritis with or without bacteremia when CD4 count less than 200 cells/mm3 with severe diarrhea.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours is recommended by the CDC as alternative therapy. The duration of therapy is 7 to 14 days for patients with CD4 count of 200 cells/mm3 or more without bacteremia, 14 days for patients with CD4 count of 200 cells/mm3 or more and bacteremia, and 2 to 6 weeks for patients with CD4 count less than 200 cells/mm3. Consider secondary prophylaxis for patients with recurrent bacteremia or recurrent gastroenteritis with or without bacteremia when CD4 count less than 200 cells/mm3 with severe diarrhea.

    Adolescents

    750 mg IV every 24 hours is recommended by the CDC as alternative therapy. The duration of therapy is 7 to 14 days for patients with CD4 count of 200 cells/mm3 or more without bacteremia, 14 days for patients with CD4 count of 200 cells/mm3 or more and bacteremia, and 2 to 6 weeks for patients with CD4 count less than 200 cells/mm3. Consider secondary prophylaxis for patients with recurrent bacteremia or recurrent gastroenteritis with or without bacteremia when CD4 count less than 200 cells/mm3 with severe diarrhea.

    For the treatment of anthrax†.
    For the treatment of cutaneous anthrax infection†.
    Oral dosage
    Adults

    750 mg PO every 24 hours. Treat for 7 to 10 days for naturally acquired infection. For a bioterrorism-related event, treat for a total duration of 60 days.

    Children and Adolescents weighing 50 kg or more

    500 mg PO every 24 hours. Treat for 7 to 10 days for naturally acquired infection. For a bioterrorism-related event, treat for a total duration of 60 days. Levofloxacin is recommended as an alternative therapy for cutaneous anthrax infection.

    Infants 6 to 11 months, Children, and Adolescents weighing less than 50 kg

    8 mg/kg/dose PO every 12 hours (Max: 250 mg/dose). Treat for 7 to 10 days for naturally acquired infection. For a bioterrorism-related event, treat for a total duration of 60 days. Levofloxacin is recommended as an alternative therapy for cutaneous anthrax infection.

    Infants 1 to 5 months

    8 mg/kg/dose PO every 12 hours. Treat for 7 to 10 days for naturally acquired infection. For a bioterrorism-related event, treat for a total duration of 60 days. Levofloxacin is recommended as an alternative therapy for cutaneous anthrax infection.

    For the treatment of systemic anthrax infection†.
    Intravenous dosage
    Adults

    750 mg IV every 24 hours. For systemic infection in which meningitis can be excluded, IV treatment should continue for at least 14 days or until clinical criteria for improvement are met. For systemic infection in which meningitis cannot be excluded, IV treatment should continue for at least 2 to 3 weeks or until clinical criteria for improvement are met. Prophylaxis to complete an antimicrobial course of up to 60 days will be required in both cases. Levofloxacin, in combination with appropriate antimicrobial therapy, is an alternative therapy for systemic anthrax infection. For systemic infection without CNS involvement, dual combination IV therapy with levofloxacin and a protein synthesis inhibitor (i.e., clindamycin, linezolid, doxycycline) or rifampin is recommended. For documented or suspected CNS infection, triple IV therapy with levofloxacin, a beta-lactam/glycopeptide, and a protein synthesis inhibitor (i.e., linezolid, clindamycin, chloramphenicol) or rifampin is recommended.

    Children and Adolescents weighing 50 kg or more

    500 mg IV every 24 hours. For systemic infection in which meningitis can be excluded, continue treatment for at least 14 days or until clinical criteria for improvement are met. For systemic infection in which meningitis cannot be excluded, continue treatment for at least 2 to 3 weeks or until clinical criteria for improvement are met. Prophylaxis to complete an antimicrobial course of up to 60 days will be required in both cases. Levofloxacin, in combination with appropriate antimicrobial therapy, is an alternative therapy for systemic anthrax infection. For systemic infection without CNS involvement, dual combination IV therapy with levofloxacin and a protein synthesis inhibitor (i.e., clindamycin, linezolid, doxycycline) is recommended. For documented or suspected CNS infection, triple IV therapy with levofloxacin, a beta-lactam/glycopeptide, and a protein synthesis inhibitor (i.e., linezolid, clindamycin) is recommended.

    Infants 6 to 11 months, Children, and Adolescents weighing less than 50 kg

    10 mg/kg/dose IV every 12 hours (Max: 250 mg/dose) for non-CNS infection; 8 mg/kg/dose IV every 12 hours (Max: 250 mg/dose) for documented/suspected CNS infection. For systemic infection in which meningitis can be excluded, continue treatment for at least 14 days or until clinical criteria for improvement are met. For systemic infection in which meningitis cannot be excluded, continue treatment for at least 2 to 3 weeks or until clinical criteria for improvement are met. Prophylaxis to complete an antimicrobial course of up to 60 days will be required in both cases. Levofloxacin, in combination with appropriate antimicrobial therapy, is an alternative therapy for systemic anthrax infection. For systemic infection without CNS involvement, dual combination IV therapy with levofloxacin and a protein synthesis inhibitor (i.e., clindamycin, linezolid, doxycycline) is recommended. For documented or suspected CNS infection, triple IV therapy with levofloxacin, a beta-lactam/glycopeptide, and a protein synthesis inhibitor (i.e., linezolid, clindamycin) is recommended.

    Infants 1 to 5 months

    10 mg/kg/dose IV every 12 hours for non-CNS infection; 8 mg/kg/dose IV every 12 hours for documented/suspected CNS infection. For systemic infection in which meningitis can be excluded, continue treatment for at least 14 days or until clinical criteria for improvement are met. For systemic infection in which meningitis cannot be excluded, continue treatment for at least 2 to 3 weeks or until clinical criteria for improvement are met. Prophylaxis to complete an antimicrobial course of up to 60 days will be required in both cases. Levofloxacin, in combination with appropriate antimicrobial therapy, is an alternative therapy for systemic anthrax infection. For systemic infection without CNS involvement, dual combination IV therapy with levofloxacin and a protein synthesis inhibitor (i.e., clindamycin, linezolid, doxycycline) is recommended. For documented or suspected CNS infection, triple IV therapy with levofloxacin, a beta-lactam/glycopeptide, and a protein synthesis inhibitor (i.e., linezolid, clindamycin) is recommended.

    Oral dosage
    Children and Adolescents weighing 50 kg or more

    500 mg PO every 24 hours. Continue treatment to complete a treatment course of at least 14 days. Additional prophylaxis to complete an antimicrobial course of up to 60 days may be required. Levofloxacin, in combination with a protein synthesis inhibitor (i.e., clindamycin, doxycycline, linezolid), is an alternative oral follow-up therapy for severe anthrax (non-CNS infection).

    Infants 6 to 11 months, Children, and Adolescents weighing less than 50 kg

    8 mg/kg/dose PO every 12 hours (Max: 250 mg/dose). Continue treatment to complete a treatment course of at least 14 days. Additional prophylaxis to complete an antimicrobial course of up to 60 days may be required. Levofloxacin, in combination with a protein synthesis inhibitor (i.e., clindamycin, doxycycline, linezolid), is an alternative oral follow-up therapy for severe anthrax (non-CNS infection).

    Infants 1 to 5 months

    8 mg/kg/dose PO every 12 hours. Continue treatment to complete a treatment course of at least 14 days. Additional prophylaxis to complete an antimicrobial course of up to 60 days may be required. Levofloxacin, in combination with a protein synthesis inhibitor (i.e., clindamycin, doxycycline, linezolid), is an alternative oral follow-up therapy for severe anthrax (non-CNS infection).

    For surgical infection prophylaxis†.
    Intravenous dosage
    Adults

    500 mg IV as a single preoperative dose for procedures involving lower urinary tract instrumentation or as an alternative option in beta-lactam allergic patients as part of combination therapy in gastrointestinal, transplantation, hysterectomy, urogynecology, and other urologic procedures. Doses should be administered within 120 minutes prior to the surgical incision. No redosing is recommended; the duration of prophylaxis should be less than 24 hours for most procedures.

    Infants, Children, and Adolescents

    10 mg/kg/dose IV as a single dose (Max: 500 mg/dose) within 120 minutes prior to the surgical incision. No redosing is recommended. Quinolones are not considered drugs of first choice in pediatric populations due to the incidence of adverse reactions. Quinolones may be used as an alternative option in a number of surgical procedures including several gastrointestinal procedures, urologic procedures, and transplantations. Generally, they are used as part of combination therapy except for procedures involving lower urinary tract instrumentation.

    For the empiric treatment of febrile neutropenia† as part of combination therapy.
    Oral dosage
    Adults

    500 to 750 mg PO once daily. Levofloxacin is not routinely recommend due to the lack of well-published data to support this indication; however, levofloxacin plus amoxicillin; clavulanate may be considered for low-risk patients.

    Intravenous dosage
    Adults

    500 to 750 mg IV once daily. Levofloxacin is not routinely recommend due to the lack of well-published data to support this indication; however, fluoroquinolones may be used as an add-on to IV therapy in certain high-risk patients.

    For the treatment of shigellosis† in HIV-infected patients.
    Oral dosage
    Adults

    750 mg PO every 24 hours is recommended by the CDC as alternative therapy. The recommended treatment duration is 7 to 10 days for gastroenteritis and at least 14 days for patients with bacteremia. Treatment is recommended up to 6 weeks for patients with recurrent infections.

    Adolescents

    750 mg PO every 24 hours is recommended by the CDC as alternative therapy. The recommended treatment duration is 7 to 10 days for gastroenteritis and at least 14 days for patients with bacteremia. Treatment is recommended up to 6 weeks for patients with recurrent infections.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours is recommended by the CDC as alternative therapy. The recommended treatment duration is 7 to 10 days for gastroenteritis and at least 14 days for patients with bacteremia. Treatment is recommended up to 6 weeks for patients with recurrent infections.

    Adolescents

    750 mg IV every 24 hours is recommended by the CDC as alternative therapy. The recommended treatment duration is 7 to 10 days for gastroenteritis and at least 14 days for patients with bacteremia. Treatment is recommended up to 6 weeks for patients with recurrent infections.

    For the treatment of campylobacteriosis† in HIV-infected patients.
    Oral dosage
    Adults

    750 mg PO every 24 hours is recommended by the CDC as alternative therapy; add an aminoglycoside for bacteremia. The recommended treatment duration is 7 to 10 days for gastroenteritis and at least 14 days for patients with bacteremia. Treatment is recommended for 2 to 6 weeks for patients with recurrent bacteremia.

    Adolescents

    750 mg PO every 24 hours is recommended by the CDC as alternative therapy; add an aminoglycoside for bacteremia. The recommended treatment duration is 7 to 10 days for gastroenteritis and at least 14 days for patients with bacteremia. Treatment is recommended for 2 to 6 weeks for patients with recurrent bacteremia.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours is recommended by the CDC as alternative therapy; add an aminoglycoside for bacteremia. The recommended treatment duration is 7 to 10 days for gastroenteritis and at least 14 days for patients with bacteremia. Treatment is recommended for 2 to 6 weeks for patients with recurrent bacteremia.

    Adolescents

    750 mg IV every 24 hours is recommended by the CDC as alternative therapy; add an aminoglycoside for bacteremia. The recommended treatment duration is 7 to 10 days for gastroenteritis and at least 14 days for patients with bacteremia. Treatment is recommended for 2 to 6 weeks for patients with recurrent bacteremia.

    For the treatment of sepsis†, including infections with difficult-to-treat resistance.
    Intravenous dosage
    Adults

    750 mg IV every 24 hours. Start within 1 hour for septic shock or within 3 hours for possible sepsis without shock. Duration of therapy is not well-defined and dependent on patient- and infection-specific factors. Assess patient daily for deescalation of antimicrobial therapy based on pathogen identification and/or adequate clinical response.

    For the treatment of traveler's diarrhea†.
    Oral dosage
    Adults

    500 mg PO as a single dose or once daily for 3 days. If symptoms are not resolved after 24 hours, continue treatment for up to 3 days. Antibiotic treatment is not recommended for mild cases, may be considered for moderate cases, and should be used for severe cases.

    For the treatment of intraabdominal infections†, including peritonitis†, appendicitis†, intraabdominal abscess†, biliary tract infections† (cholecystitis†, cholangitis†), complicated diverticulitis†, peritoneal dialysis-related peritonitis†, peritoneal dialysis catheter-related infection†.
    For the treatment of peritoneal dialysis-related peritonitis†.
    Oral dosage
    Adults

    250 mg PO every 24 hours for 21 to 28 days.

    For the treatment of complicated community-acquired and healthcare-acquired intraabdominal infections† with adequate source control.
    Oral dosage
    Adults

    500 to 750 mg PO every 24 hours as part of combination therapy for 3 to 7 days. Complicated infections include peritonitis and appendicitis complicated by rupture, intraabdominal abscess, and complicated diverticulitis .

    Children and Adolescents weighing 50 kg or more

    500 mg PO every 24 hours as part of combination therapy for 3 to 7 days. Complicated infections include peritonitis and appendicitis complicated by rupture, and intraabdominal abscess.

    Infants, Children, and Adolescents 6 months to 17 years weighing less than 50 kg

    8 to 10 mg/kg/dose (Max: 250 mg/dose) PO every 12 hours as part of combination therapy for 3 to 7 days. Complicated infections include peritonitis and appendicitis complicated by rupture, and intraabdominal abscess.

    Intravenous dosage
    Adults

    500 to 750 mg IV every 24 hours as part of combination therapy for 3 to 7 days. Complicated infections include peritonitis and appendicitis complicated by rupture, and intraabdominal abscess.

    Children and Adolescents weighing 50 kg or more

    500 mg IV every 24 hours as part of combination therapy for 3 to 7 days. Complicated infections include peritonitis and appendicitis complicated by rupture, and intraabdominal abscess.

    Infants, Children, and Adolescents 6 months to 17 years weighing less than 50 kg

    8 to 10 mg/kg/dose (Max: 250 mg/dose) IV every 12 hours as part of combination therapy for 3 to 7 days. Complicated infections include peritonitis and appendicitis complicated by rupture, and intraabdominal abscess.

    For the treatment of uncomplicated intraabdominal infections†.
    Oral dosage
    Adults

    500 to 750 mg PO once as part of combination therapy. Antibiotics should be discontinued within 24 hours. Uncomplicated infections include acute appendicitis without perforation, abscess, or local peritonitis; traumatic bowel perforations repaired within 12 hours; acute cholecystitis without perforation; and ischemic, non-perforated bowel.

    Children and Adolescents weighing 50 kg or more

    500 mg PO once as part of combination therapy. Antibiotics should be discontinued within 24 hours. Uncomplicated infections include acute appendicitis without perforation, abscess, or local peritonitis; traumatic bowel perforations repaired within 12 hours; acute cholecystitis without perforation; and ischemic, non-perforated bowel.

    Infants, Children, and Adolescents 6 months to 17 years weighing less than 50 kg

    8 to 10 mg/kg/dose (Max: 250 mg/dose) PO every 12 hours as part of combination therapy. Antibiotics should be discontinued within 24 hours. Uncomplicated infections include acute appendicitis without perforation, abscess, or local peritonitis; traumatic bowel perforations repaired within 12 hours; acute cholecystitis without perforation; and ischemic, non-perforated bowel.

    Intravenous dosage
    Adults

    500 to 750 mg IV once as part of combination therapy. Antibiotics should be discontinued within 24 hours. Uncomplicated infections include acute appendicitis without perforation, abscess, or local peritonitis; traumatic bowel perforations repaired within 12 hours; acute cholecystitis without perforation; and ischemic, non-perforated bowel.

    Children and Adolescents weighing 50 kg or more

    500 mg IV once as part of combination therapy. Antibiotics should be discontinued within 24 hours. Uncomplicated infections include acute appendicitis without perforation, abscess, or local peritonitis; traumatic bowel perforations repaired within 12 hours; acute cholecystitis without perforation; and ischemic, non-perforated bowel.

    Infants, Children, and Adolescents 6 months to 17 years weighing less than 50 kg

    8 to 10 mg/kg/dose (Max: 250 mg/dose) IV every 12 hours as part of combination therapy. Antibiotics should be discontinued within 24 hours. Uncomplicated infections include acute appendicitis without perforation, abscess, or local peritonitis; traumatic bowel perforations repaired within 12 hours; acute cholecystitis without perforation; and ischemic, non-perforated bowel.

    For the treatment of peritoneal dialysis catheter-related infection†.
    Oral dosage
    Adults

    250 mg PO every 24 hours for at least 14 to 21 days.

    Infants, Children, and Adolescents

    10 mg/kg/dose PO every 48 hours (Max: 500 mg on day 1 then 250 mg) for at least 14 to 28 days.

    For the treatment of complicated community-acquired and healthcare-acquired intraabdominal infections† with adequate source control due to resistant gram-negative organisms.
    Oral dosage
    Adults

    750 mg PO every 24 hours as part of combination therapy for 3 to 7 days. Complicated infections include peritonitis and appendicitis complicated by rupture, and intraabdominal abscess.

    Intravenous dosage
    Adults

    750 mg IV every 24 hours as part of combination therapy for 3 to 7 days. Complicated infections include peritonitis and appendicitis complicated by rupture, and intraabdominal abscess.

    For bacterial infection prophylaxis† in high-risk pediatric cancer patients.
    NOTE: Consider prophylaxis in pediatric patients with AML or relapsed ALL receiving intensive chemotherapy expected to result in severe neutropenia (absolute neutrophil count (ANC) less than 500 cells/mm3) for at least 7 days. Routine prophylaxis is not recommended for patients receiving induction chemotherapy for newly diagnosed ALL, patients whose therapy is not expected to result in severe neutropenia for at least 7 days, or for patients undergoing HSCT.
    Oral dosage
    Children and Adolescents 5 to 17 years

    10 mg/kg/dose PO every 24 hours (Max: 750 mg/day) continued through the period of severe neutropenia (ANC less than 500 cells/mm3).

    Infants and Children 6 months to 4 years

    10 mg/kg/dose PO every 12 hours continued through the period of severe neutropenia (ANC less than 500 cells/mm3).

    Intravenous dosage
    Children and Adolescents 5 to 17 years

    10 mg/kg/dose IV every 24 hours (Max: 750 mg/day) continued through the period of severe neutropenia (ANC less than 500 cells/mm3).

    Infants and Children 6 months to 4 years

    10 mg/kg/dose IV every 12 hours continued through the period of severe neutropenia (ANC less than 500 cells/mm3).

    For the treatment of drug-resistant tuberculosis infection† as part of combination therapy.
    Oral dosage
    Adults

    750 to 1,000 mg PO once daily; doses up to 1,250 mg PO once daily have been used safely when needed to achieve therapeutic concentrations.[34362] [65465] [65620]

    Infants, Children, and Adolescents

    15 to 20 mg/kg/dose PO once daily. A pharmacokinetic study found that doses from 18 mg/kg/day PO for younger children, up to 40 mg/kg/day PO for older children may be required to achieve adult-equivalent exposures.

    Intravenous dosage
    Adults

    750 to 1,000 mg IV once daily; doses up to 1,250 mg IV once daily have been used safely when needed to achieve therapeutic concentrations.

    Infants, Children, and Adolescents

    15 to 20 mg/kg/dose IV once daily. A pharmacokinetic study found that doses from 18 mg/kg/day IV for younger children, up to 40 mg/kg/day IV for older children may be required to achieve adult-equivalent exposures.

    †Indicates off-label use

    MAXIMUM DOSAGE

    Adults

    750 mg/day PO/IV; 1,250 mg/day PO/IV has been used off-label.

    Geriatric

    750 mg/day PO/IV; 1,250 mg/day PO/IV has been used off-label.

    Adolescents

    weight 50 kg or more: 500 mg/day PO/IV is FDA-approved; however, doses up to 20 mg/kg/day PO/IV (Usual Max: 1,000 mg/day) have been used off-label.
    weight less than 50 kg: 16 mg/kg/day PO/IV (Max: 500 mg/day or 250 mg/dose) is FDA-approved; however, doses up to 20 mg/kg/day PO/IV (Usual Max: 1,000 mg/day) have been used off-label.

    Children

    weight 50 kg or more: 500 mg/day PO/IV is FDA-approved; however, doses up to 20 mg/kg/day PO/IV (Max: 1,000 mg/day) have been used off-label.
    weight less than 50 kg: 16 mg/kg/day PO/IV (Max: 500 mg/day or 250 mg/dose) is FDA-approved; however, doses up to 20 mg/kg/day PO/IV (Max: 1,000 mg/day) have been used off-label.

    Infants

    6 to 11 months: 16 mg/kg/day PO/IV is FDA-approved; however, doses up to 20 mg/kg/day PO/IV have been used off-label.
    1 to 5 months: Safety and efficacy have not been established; however, doses up to 20 mg/kg/day PO/IV have been used off-label.

    Neonates

    Safety and efficacy have not been established.

    DOSING CONSIDERATIONS

    Hepatic Impairment

    No dosage adjustment needed.

    Renal Impairment

    Adult patients with a usual dose of 750 mg IV or PO every 24 hours (FDA-approved labeling) [63729] [65562]
    CrCl 50 mL/minute or more: No dosage adjustment needed.
    CrCl 20 to 49 mL/minute: 750 mg IV or PO every 48 hours.
    CrCl 10 to 19 mL/minute: 750 mg IV or PO once, then 500 mg IV or PO every 48 hours.
     
    Adult patients with a usual dose of 500 mg IV or PO every 24 hours (FDA-approved labeling) [63729] [65562]
    CrCl 50 mL/minute or more: No dosage adjustment needed.
    CrCl 20 to 49 mL/minute: 500 mg IV or PO once, then 250 mg IV or PO every 24 hours.
    CrCl 10 to 19 mL/minute: 500 mg IV or PO once, then 250 mg IV or PO every 48 hours.
     
    Adult patients with a usual dose of 250 mg IV or PO every 24 hours (FDA-approved labeling) [63729] [65562]
    CrCl 20 mL/minute or more: No dosage adjustment needed.
    CrCl 10 to 19 mL/minute: 250 mg IV or PO every 48 hours except when treating uncomplicated UTI, then no dosage adjustment needed.
     
    Adult patients receiving therapy for tuberculosis† [61094] [65465]
    CrCl 30 mL/minute or more: No dosage adjustment needed.
    CrCl less than 30 mL/minute: 750 to 1,000 mg IV or PO 3 times weekly.
     
    Pediatric patients† [32569]
    NOTE: The following dose adjustments are based on a usual pediatric dose of 5 to 10 mg/kg/dose (Max: 750 mg/dose) IV or PO every 12 hours for children 5 years and younger and 5 to 10 mg/kg/dose (Max: 750 mg/dose) IV or PO every 24 hours for children older than 5 years.
    GFR 30 mL/minute/1.73 m2 or more: No dosage adjustment necessary.
    GFR 10 to 29 mL/minute/1.73 m2: 5 to 10 mg/kg/dose (Max: 750 mg/dose) IV or PO every 24 hours for all ages.
    GFR less than 10 mL/minute/1.73 m2: 5 to 10 mg/kg/dose (Max: 750 mg/dose) IV or PO every 48 hours for all ages.
     
    Pediatric patients receiving therapy for tuberculosis† [61094] [65465]
    CrCl 30 mL/minute or more: No dosage adjustment needed.
    CrCl less than 30 mL/minute: 15 to 20 mg/kg/dose (Max: 1,000 mg/dose) IV or PO 3 times weekly.
     
    Intermittent hemodialysis
    NOTE: Levofloxacin is not effectively removed during hemodialysis.[63729] [65562]
     
    Adult patients with a usual dose of 750 mg IV or PO every 24 hours (FDA-approved labeling)
    750 mg IV or PO once, then 500 mg IV or PO every 48 hours.[63729] [65562]
     
    Adult patients with a usual dose of 500 mg IV or PO every 24 hours (FDA-approved labeling)
    500 mg IV or PO once, then 250 mg IV or PO every 48 hours.[63729] [65562]
     
    Adult patients with a usual dose of 250 mg IV or PO every 24 hours (FDA-approved labeling)
    No information is available for dosage adjustment.[63729] [65562]
     
    Adult patients receiving therapy for tuberculosis†
    750 to 1,000 mg IV or PO 3 times weekly.[61094] [65465]
     
    Pediatric patients†
    5 to 10 mg/kg/dose (Max: 750 mg/dose) IV or PO every 48 hours.[32569]
     
    Pediatric patients receiving therapy for tuberculosis†
    15 to 20 mg/kg/dose (Max: 1,000 mg/dose) IV or PO 3 times weekly.[61094] [65465]
     
    Peritoneal dialysis
    NOTE: Levofloxacin is not effectively removed during peritoneal dialysis.[63729] [65562]
     
    Adult patients with a usual dose of 750 mg IV or PO every 24 hours (FDA-approved labeling)
    750 mg IV or PO once, then 500 mg IV or PO every 48 hours.[63729] [65562]
     
    Adult patients with a usual dose of 500 mg IV or PO every 24 hours (FDA-approved labeling)
    500 mg IV or PO once, then 250 mg IV or PO every 48 hours.[63729] [65562]
     
    Adult patients with a usual dose of 250 mg IV or PO every 24 hours (FDA-approved labeling)
    No information is available for dosage adjustment.[63729] [65562]
     
    Pediatric patients†
    5 to 10 mg/kg/dose (Max: 750 mg/dose) IV or PO every 48 hours.[32569]
     
    Hybrid hemodialysis†
    NOTE: Hybrid hemodialysis modalities include prolonged intermittent renal replacement therapy (PIRRT), sustained low-efficiency dialysis (SLED), slow extended daily dialysis/diafiltration (SLEDD-f), and extended daily dialysis (EDD). Dosing should take into consideration patient-specific factors (e.g., intrinsic renal function), the type of infection, the duration of renal replacement therapy, the ultrafiltration rate, the dialysis flow rate, and how often dialysis sessions occur.[65397]
     
    Adult patients
    PIRRT: Levofloxacin is not recommended as empiric monotherapy for serious gram-negative infections in patients receiving PIRRT due to suboptimal efficacy; however, when used in combination with another primary antibiotic for gram-negative infections, levofloxacin 750 mg IV once, then 750 mg IV post-PIRRT is recommended. For gram-positive infections, 750 mg IV once, then 500 mg IV post-PIRRT achieved about 90% probability of target attainment with an 8-hour PIRRT session. In an in silico trial using Monte Carlo simulation, levofloxacin dosing was studied using 4 different PIRRT setting simulations over 8 to 10 hours/day.[65425]
    EDD: Administer levofloxacin after EDD. In a pharmacokinetic study of 5 critical care patients receiving an 8-hour EDD session, dialysis removed 20% to 30% of levofloxacin.[65426]
     
    Continuous renal replacement therapy (CRRT)†
    NOTE: Various CRRT modalities include continuous venovenous hemofiltration (CVVH), continuous venovenous hemodialysis (CVVHD), continuous venovenous hemodiafiltration (CVVHDF), continuous venovenous high-flux hemodialysis (CVVHFD), continuous arteriovenous hemofiltration (CAVH), continuous arteriovenous hemodialysis (CAVHD), and continuous arteriovenous hemodiafiltration (CAVHDF). Dosing should take into consideration patient-specific factors (e.g. intrinsic renal function), type of infection, the duration of renal replacement therapy, the effluent flow rate, and the replacement solution administered.[42303]
     
    Adult patients
    In general, 500 mg IV or PO every 48 hours or 500 or 750 mg IV or PO once, then 250 or 500 mg IV every 24 has been suggested for CRRT.[32569] [65399]
    CVVH: 500 or 750 mg IV or PO once, then 250 mg IV or PO every 24 hours.
    CVVHD: 500 or 750 mg IV or PO once, then 250 or 500 mg IV or PO every 24 hours.
    CVVHDF: 500 or 750 mg IV or PO once, then 250 to 750 mg IV or PO every 24 hours.[34038] [42303]
     
    Pediatric patients
    10 mg/kg/dose (Max: 750 mg/dose) IV or PO every 24 hours.[32569]

    ADMINISTRATION

     
    Tuberculosis patients†
    Directly observed therapy (DOT) is recommended for all children as well as adolescents and adults living with HIV.[34361] [34362] [61094]

    Oral Administration

    If a dose is missed, take it as soon as possible anytime up to 8 hours before the next scheduled dose. If less than 8 hours remain before the next dose, wait until the next scheduled dose.

    Oral Solid Formulations

    Tablets: Levofloxacin tablets can be taken with or without food; however, administer at least 2 hours before or 2 hours after any antacid, multivitamin, or other medication that contains divalent or trivalent cations.

    Oral Liquid Formulations

    Oral solution: Administer 1 hour before or 2 hours after eating and at least 2 hours before or 2 hours after any antacid, multivitamin, or other medication that contains divalent or trivalent cations.

    Injectable Administration

    Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.

    Intravenous Administration

    Vials
    Dilution
    Withdraw appropriate dose from vial (25 mg/mL) and dilute with a compatible intravenous solution to a concentration of 5 mg/mL.
    250 mg dose: Withdraw 10 mL and dilute with 40 mL.
    500 mg dose: Withdraw 20 mL and dilute with 80 mL.
    750 mg dose: Withdraw 30 mL and dilute with 120 mL.
    Compatible diluents include 0.9% Sodium Chloride Injection, 5% Dextrose Injection, 5% Dextrose and 0.9% Sodium Chloride Injection, 5% Dextrose in Lactated Ringers Injection, Plasma-Lyte 56/5% Dextrose Injection, 5% Dextrose and 0.45% Sodium Chloride and 0.15% Potassium Chloride Injection, and Sodium Lactate Injection (M/6).
    If more than 1 dose is to be prepared from a single vial, withdraw the full contents of the vial at once using a single-entry procedure; prepare and store the additional dose(s) for subsequent use.
    Storage: Vials are for single-dose only; discard any ununsed portion. The diluted solution may be stored for up to 72 hours when kept at or below 25 degrees C (77 degrees F) or for 14 days when stored under refrigeration at 5 degrees C (41 degrees F) in plastic containers. Solutions may be frozen for up to 6 months (-20 degrees C or -4 degrees F) in glass bottles or plastic containers. Thaw frozen solutions at room temperature (25 degrees C or 77 degrees F) or in the refrigerator (8 degrees C or 46 degrees F). Do not force thaw by microwave or water bath immersion. Do not refreeze after initial thawing.[61195]
     
    Premixed IV Solution
    No dilution is necessary.
    Do not use flexible containers in series connections.[63729]
     
    Intermittent IV infusion
    Infusion time varies by dose.
    250 or 500 mg dose: Infuse over 60 minutes.
    750 mg dose: Infuse over 90 minutes.
    Avoid shorter infusions or bolus injections because of the risk of hypotension.[61195] [63729]

    Ophthalmic Administration

    Apply topically to the eye taking care to avoid contamination. For ophthalmic use only. Do not inject subconjunctivally or introduce directly into the anterior chamber of the eye.
    Instruct patient on proper instillation of ophthalmic solution.
    Do not touch the tip of the dropper to the eye, fingertips, or other surface.

    STORAGE

    Iquix:
    - Store between 59 to 77 degrees F
    Levaquin:
    - Store at controlled room temperature (between 68 and 77 degrees F)
    Levaquin Leva-Pak:
    - Store at controlled room temperature (between 68 and 77 degrees F)
    Quixin:
    - Store at controlled room temperature (between 68 and 77 degrees F)

    CONTRAINDICATIONS / PRECAUTIONS

    Quinolone hypersensitivity

    Levofloxacin is contraindicated in patients with known quinolone hypersensitivity. Serious and occasionally fatal hypersensitivity and/or anaphylactic reactions have occurred even after the first dose of the drug. Some reactions were accompanied by cardiovascular collapse, loss of consciousness, tingling, pharyngeal or facial edema, dyspnea, urticaria, and pruritus. Discontinue levofloxacin immediately at the first appearance of a skin rash or any other sign of hypersensitivity. Serious anaphylactic reactions require immediate emergency treatment with epinephrine. Administer oxygen, intravenous steroids, and airway management, including intubation, as indicated.

    Corticosteroid therapy, organ transplant, tendinitis, tendinopathy, tendon pain, tendon rupture

    Systemic quinolones have been associated with disabling and potentially irreversible serious adverse reactions such as tendinopathy, including tendinitis and tendon rupture requiring surgical repair or resulting in prolonged disability. These reactions can occur within hours to weeks after starting these agents in patients of any age, with or without pre-existing risk factors. Because of this risk for serious and potentially permanent side effects, quinolones should only be used for the treatment of uncomplicated urinary tract infection, acute bacterial exacerbation of chronic bronchitis, or acute bacterial sinusitis in cases where alternative treatment options cannot be used. Discontinue quinolones at the first sign of tendon inflammation or tendon pain as these are symptoms that may precede rupture of the tendon. Avoid quinolone use in patients with a history of tendon disorders or tendon rupture. Tendon rupture typically involves the Achilles tendon; however, ruptures of the hand, shoulder, biceps, thumb, and other tendons have also been reported. Tendinitis and tendon rupture can occur bilaterally. Rupture can occur during therapy or up to a few months after therapy has been stopped. The risk of tendon rupture is increased in older adults over 60 years of age, those receiving concomitant corticosteroid therapy, and in organ transplant recipients (including kidney, heart, and lung transplants). Other reasons for tendon ruptures include physical activity or exercise, kidney failure, or tendon problems in the past. If patients experience tendon inflammation or pain, they should rest and refrain from exercise until the diagnosis of tendonitis or tendon rupture has been confidently excluded.

    Arteriosclerosis, cerebrovascular disease, depression, neurotoxicity, peripheral neuropathy, psychiatric event, seizure disorder

    Systemic quinolones have been associated with disabling and potentially irreversible serious neurotoxicity, including central nervous system effects, peripheral neuropathy, or psychiatric event. These reactions can occur within hours to weeks after starting these agents in patients of any age, with or without pre-existing risk factors. Because of this risk for serious and potentially permanent side effects, use quinolones for the treatment of uncomplicated urinary tract infection, acute bacterial exacerbation of chronic bronchitis, or acute bacterial sinusitis only in cases where alternative treatment options cannot be used. Avoid quinolone use in patients who have previously experienced peripheral neuropathy. Additionally, use quinolones with caution in patients with a known or suspected CNS disorder (e.g., severe cerebrovascular disease or arteriosclerosis, seizure disorder) or in the presence of other risk factors (e.g., certain drug therapy, renal dysfunction) that may predispose to seizures or lower seizure threshold. Attempted or completed suicide has been reported, especially in patients with a history of depression, or an underlying risk factor for depression. Discontinue quinolone therapy at the first signs or symptoms of neuropathy (e.g., pain, burning, tingling, numbness, and/or weakness, or other alterations in sensations such as light touch, pain, temperature, position sense, and vibratory sensation, and/or motor strength), central nervous system adverse events (seizures or convulsions, increased intracranial pressure (including pseudotumor cerebri), dizziness, or tremors), or psychiatric adverse events (toxic psychosis, hallucinations, paranoia, depression, suicidal thoughts or acts, confusion, delirium, disorientation, disturbances in attention, anxiety, agitation, nervousness, insomnia, nightmares, or memory impairment).

    Myasthenia gravis

    Avoid use of systemic quinolones, such as levofloxacin, in patients with a history of myasthenia gravis. Systemic quinolones may exacerbate the signs of myasthenia gravis and lead to life threatening weakness of the respiratory muscles. Serious postmarketing events, including deaths and the requirement for ventilatory support, have been associated with quinolone use in patients with myasthenia gravis. Because of this risk for serious and potentially permanent side effects, quinolones should only be used for the treatment of uncomplicated urinary tract infection, acute bacterial exacerbation of chronic bronchitis, or acute bacterial sinusitis in cases where alternative treatment options cannot be used.

    Apheresis, atrial fibrillation, AV block, bradycardia, cardiac arrhythmias, cardiomyopathy, celiac disease, females, fever, heart failure, human immunodeficiency virus (HIV) infection, hyperparathyroidism, hypocalcemia, hypokalemia, hypomagnesemia, hypothermia, hypothyroidism, long QT syndrome, myocardial infarction, pheochromocytoma, QT prolongation, rheumatoid arthritis, sickle cell disease, sleep deprivation, stroke, systemic lupus erythematosus (SLE), torsade de pointes

    Levofloxacin should be used cautiously in patients with cardiac arrhythmias or other cardiac disease that predisposes to cardiac arrhythmias. Fluoroquinolones have the potential to cause QT prolongation and possibly torsade de pointes (TdP) by blocking human cardiac potassium (K+) channel currents.[28775] [33146] The potency of this blockade varies among the quinolones. Levofloxacin blocks human cardiac K+ channels at potencies greater than that of ciprofloxacin and ofloxacin but less than that of moxifloxacin.[33146] Based on cardiac studies, clinical trials, and postmarketing evaluations, the overall risk for TdP appears to be similar between levofloxacin and moxifloxacin.[28419] [28775] [29833] [33144] [33145] [48869] [48871] [48872] During postmarketing surveillance, rare cases of TdP have been spontaneously reported in patients receiving quinolones, including levofloxacin.[29833] The unmonitored use of quinolones in patients with a stable ischemic heart and preserved left ventricular function is likely safe and the risk of QT prolongation and TdP is low.[33141] However, avoid the unmonitored use of quinolones in patients with known QT prolongation, patients with ongoing proarrhythmic conditions that may increase the risk of developing TdP (e.g., uncorrected hypokalemia or hypomagnesemia, significant bradycardia, congestive heart failure, acute myocardial ischemia, and atrial fibrillation), or patients receiving medications known to prolong the QT interval.[28421] [43378] Use levofloxacin with caution in patients with conditions that may increase the risk of QT prolongation including congenital long QT syndrome, bradycardia, AV block, heart failure, stress-related cardiomyopathy, myocardial infarction, stroke, hypomagnesemia, hypokalemia, hypocalcemia, or in patients receiving medications known to prolong the QT interval or cause electrolyte imbalances. Females, people 65 years and older, patients with sleep deprivation, pheochromocytoma, sickle cell disease, hypothyroidism, hyperparathyroidism, hypothermia, systemic inflammation (e.g., human immunodeficiency virus (HIV) infection, fever, and some autoimmune diseases including rheumatoid arthritis, systemic lupus erythematosus (SLE), and celiac disease) and patients undergoing apheresis procedures (e.g., plasmapheresis [plasma exchange], cytapheresis) may also be at increased risk for QT prolongation.[28432] [28457] [56592] Silent mutations and genetic polymorphisms in potassium channels may further increase the risk of QT prolongation in patients taking quinolones.[33148] [33149] If a quinolone is desired in patients with risk factors for QT prolongation, the use of ciprofloxacin is preferable, with ECG monitoring at initiation of therapy. If other quinolones are used, ECG and/or Holter monitoring during therapy is recommended.[33141]

    Renal failure, renal impairment

    Clearance of levofloxacin is substantially reduced and plasma elimination half-life is substantially prolonged in patients with renal impairment, as evidenced by a creatinine clearance (CrCl) less than 50 mL/minute. Dosage adjustment of levofloxacin is required in such patients, including patients with renal failure or receiving dialysis, to avoid accumulation.

    Dehydration

    Systemic levofloxacin should be used with caution in patients with dehydration. Although levofloxacin is more soluble than other quinolones, adequate hydration should be maintained to ensure the formation of a dilute urine, thereby preventing crystalluria.

    Hepatic disease, hepatitis, hepatotoxicity, jaundice

    Use levofloxacin with caution in patients at risk for or with pre-existing hepatic disease. Cases of severe hepatotoxicity, including acute hepatitis and fatalities, have been reported in patients receiving systemic levofloxacin. Hepatotoxicity generally occurred within 14 days of initiating therapy with most cases occurring within 6 days. Most cases were not associated with hypersensitivity. The majority of fatal cases were reported in patients 65 years of age and older. Discontinue levofloxacin immediately if the patient develops signs and symptoms of hepatitis (e.g., jaundice, right upper abdominal pain, fatigue, nausea, vomiting, dark colored urine, light colored stools).

    Diabetes mellitus

    Blood glucose disturbances, including symptomatic hyperglycemia and hypoglycemia, have been reported in patients receiving systemic levofloxacin. Hypoglycemia, sometimes resulting in coma, occurs more frequently in elderly patients or patients with diabetes mellitus who are receiving an oral hypoglycemic agent or insulin concomitantly with levofloxacin; carefully monitor blood glucose concentrations in these patients. Educate patients on the symptoms of hypoglycemia and how to treat if they experience hypoglycemia. Discontinue levofloxacin if a hypoglycemic reaction occurs and initiate appropriate therapy immediately.  Patients with diabetes may also be at an increased risk of developing detachment of the retina.

    Sunlight (UV) exposure

    Moderate to severe phototoxicity reactions have been observed in patients exposed to direct sunlight while receiving a systemic fluoroquinolone, such as levofloxacin. Although phototoxicity has occurred only rarely during levofloxacin therapy, patients should avoid excessive sunlight (UV) exposure. Therapy should be discontinued if phototoxicity occurs.

    C. difficile-associated diarrhea, diarrhea, pseudomembranous colitis

    Consider pseudomembranous colitis in patients presenting with diarrhea after antibacterial use. Careful medical history is necessary as pseudomembranous colitis has been reported to occur over 2 months after the administration of antibacterial agents. Almost all antibacterial agents, including levofloxacin, have been associated with pseudomembranous colitis or C. difficile-associated diarrhea (CDAD) which may range in severity from mild to life-threatening. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile.

    Aneurysm, aortic dissection, hypertension

    Reserve systemic quinolones for use only when there are no alternative antibacterial treatments available in patients at risk for aortic dissection, including those with a history of aneurysm of the aorta or other blood vessels, peripheral atherosclerotic vascular diseases, hypertension, certain genetic conditions such as Marfan syndrome and Ehlers-Danlos syndrome, and elderly patients. Epidemiologic studies report an increased rate of aortic dissection within 2 months after quinolone use, particularly in elderly patients. 

    Geriatric

    Geriatric patients may be at a higher risk of adverse events related to systemic quinolones. Geriatric patients are more likely to have decreased renal function and care should be taken in dose selection; it may be useful to monitor renal function. Cases of fatal hepatotoxicity, not related to hypersensitivity reactions, have occurred in older adults (65 years and older) taking levofloxacin. Older adult patients are also at increased risk of developing tendon disorders while receiving quinolones; concomitant use of corticosteroids further increases these risks. Elderly patients may also be more susceptible to drug-associated effects on the QT interval and aortic dissection.  The federal Omnibus Budget Reconciliation Act (OBRA) regulates medication use in residents of long-term care facilities (LTCFs); limit antibiotic use to confirmed or suspected bacterial infections. Antibiotics are non-selective and may result in the eradication of beneficial microorganisms while promoting the emergence of undesired ones, causing secondary infections such as oral thrush, colitis, or vaginitis. Monitor for GI side effects and hypersensitivity reactions. Fluoroquinolones may increase the risk of acute tendonitis, a prolonged QT interval, or the risk of hypoglycemia/hyperglycemia in adults 65 years or older. Per OBRA, use should be avoided in individuals with prolonged QTc intervals or who are receiving selected antiarrhythmic agents.[60742]

    Children, infants, neonates

    Caution is warranted with the systemic use of quinolones such as levofloxacin in neonates, infants, children, and adolescents. Systemic quinolones cause arthropathy in juvenile animals of several species. Evidence supporting sustained injury to developing joints in humans is lacking at this time; however, the possibility of rare occurrences has not been excluded.  Topical ocular administration to the eye is approved for Quixin solution for children as young as 1 year of age and for Iquix for children as young as 6 years of age; there is no evidence that the ophthalmic administration of levofloxacin has any effect on weight bearing joints. One retrospective study compared the rate of tendon or joint disorders in more than 7,000 children less than 19 years old who received ciprofloxacin, ofloxacin, or levofloxacin with more than 20,000 children who received azithromycin. The incidence of potential tendon or joint disorders was found to be approximately 2% in both the quinolone and azithromycin groups, and verified disorders were reported in less than 1% in both groups. The authors state that this incidence is likely to reflect the background incidence of these disorders in pediatric patients. Another published report evaluated the safety data collected from 2,523 children and adolescents who participated in 1 of 3 efficacy trials and were randomized to receive levofloxacin or nonquinolone antibiotics. Two of the trials were open-label and 1 was evaluator-blinded only. In addition, a subset of these children participated in a 1-year surveillance trial (n = 2,233). The safety analysis focused on 4 musculoskeletal disorders: arthralgia, arthritis, tendinopathy, and gait abnormality. The authors reported an odds ratio and 95% confidence interval of 2.2 (0.95 to 5.2) at 1 month and 1.9 (1.1 to 3.5) at 1 year for experiencing at least 1 of the 4 musculoskeletal disorders as reported by the patient or parent or evaluated by an investigator. Due to concerns of increasing bacterial resistance, the possibility of rare joint injury, and other possible serious adverse reactions (i.e., CNS effects, peripheral neuropathy), the American Academy of Pediatrics Committee on Infectious Diseases recommends reserving the use of systemic quinolones for infections caused by multidrug-resistant pathogens for which there is no safe and effective alternative, for the treatment of infections when parenteral therapy is not feasible and no other effective oral agent is available, and for the treatment of infections as an alternative to standard therapy because of concerns for antimicrobial resistance, toxicity, or characteristics of tissue penetration.

    Contact lenses

    Whenever clinical judgment dictates, examine patients receiving ophthalmic levofloxacin with the aid of magnification, such as slit lamp biomicroscopy, and, where appropriate, fluorescein staining. Advise patients not to wear contact lenses if they have signs and symptoms of bacterial conjunctivitis.

    Driving or operating machinery

    Systemic levofloxacin can cause dizziness and light-headedness; therefore, patients should know how they react to the drug before driving or operating machinery or engaging in an activity requiring mental alertness or coordination.

    Laboratory test interference

    Administration of levofloxacin may result in laboratory test interference. False positive urine screening results for opiates have been reported in patients using some quinolones. These false positives are more likely to occur with levofloxacin and ofloxacin when used clinically because they produce urinary concentrations sufficient to interfere with commercially available immunoassay kits. Confirmation of positive opiate screens by more specific methods may be necessary. Antimicrobials are also known to suppress H. pylori; thus, ingestion of these agents within 4 weeks of performing diagnostic tests for H. pylori may lead to false negative results. At a minimum, instruct the patient to avoid the use of levofloxacin in the 4 weeks prior to the test.

    Pregnancy

    Published information on levofloxacin administration during pregnancy have not identified any drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes.  In a nested, case-control study (n = 87,020 controls; 8,702 cases) within the Quebec Pregnancy Cohort, quinolone use during early pregnancy was associated with an increased risk of spontaneous abortion (adjusted odds ratio (aOR) 2.72; 95% CI: 2.27 to 3.27; 160 exposed cases); residual confounding by severity of infection may be a potential limitation of this study.[62176] In a large population-based cohort study (n = 139,938 live births) assessing antibiotic exposure during the first trimester of pregnancy (n = 15,469 exposures) and the risk of major birth defects, quinolone use was associated with an increased risk of urinary system malformations (aOR 1.89; 95% CI: 1.09 to 3.28, 14 exposed cases).[62177]

    Breast-feeding

    Levofloxacin is present in human breast milk after systemic administration. There is no information regarding the effects of levofloxacin on milk production or the breast-fed infant. Because of the potential risks of serious adverse reactions in breast-fed infants, breast-feeding is not recommended during treatment with levofloxacin and for an additional 2 days (5 half-lives) after the last dose. A lactating woman may consider pumping and discarding breast milk during treatment with levofloxacin and for an additional 2 days after the last dose.[63729] [65562] During an incident resulting in exposure to anthrax, the risk-benefit assessment of continuing breast-feeding while the mother is receiving levofloxacin may be acceptable; consider the developmental and health benefits of breast-feeding along with the mother's clinical need for levofloxacin and any potential adverse effects on the breast-fed child from levofloxacin or the underlying maternal condition.[28421] In a single case report, the peak levofloxacin breast milk concentration in a woman receiving 500 mg IV was 8.2 mcg/mL at 5 hours after the dose. The estimated maximum daily dose of levofloxacin through breast-feeding that an infant fed exclusively with breast milk (approximately 900 mL/day) would receive is 5 mg (approximately 1% of the maternal daily dose).[63729] [65562] Ciprofloxacin, sulfamethoxazole; trimethoprim, ceftazidime, ceftriaxone, cefepime, and piperacillin; tazobactam may be potential systemic alternatives to consider during breast-feeding. However, site of infection, patient factors, local susceptibility patterns, and specific microbial susceptibility should be assessed before choosing an alternative agent.[27500] Other beta-lactams, such as cefepime and piperacillin; tazobactam are generally considered compatible with breast-feeding.[46945] [46946] [46947] Use caution when administering the levofloxacin ophthalmic solution to a breast-feeding mother; however, the systemic absorption after topical ocular administration is minimal and would not be expected to result in clinically significant breast milk concentrations.[40311]

    ADVERSE REACTIONS

    Severe

    visual impairment / Early / 1.0-3.0
    pancreatitis / Delayed / 0.1-1.0
    renal failure (unspecified) / Delayed / 0.1-1.0
    seizures / Delayed / 0.1-1.0
    cardiac arrest / Early / 0.1-1.0
    ventricular tachycardia / Early / 0.1-1.0
    hyperkalemia / Delayed / 0.1-1.0
    headache / Early / 0.2-0.3
    interstitial nephritis / Delayed / Incidence not known
    serum sickness / Delayed / Incidence not known
    erythema multiforme / Delayed / Incidence not known
    anaphylactic shock / Rapid / Incidence not known
    bronchospasm / Rapid / Incidence not known
    laryngeal edema / Rapid / Incidence not known
    acute generalized exanthematous pustulosis (AGEP) / Delayed / Incidence not known
    Stevens-Johnson syndrome / Delayed / Incidence not known
    rhabdomyolysis / Delayed / Incidence not known
    toxic epidermal necrolysis / Delayed / Incidence not known
    angioedema / Rapid / Incidence not known
    anaphylactoid reactions / Rapid / Incidence not known
    vasculitis / Delayed / Incidence not known
    thrombotic thrombocytopenic purpura (TTP) / Delayed / Incidence not known
    hepatic necrosis / Delayed / Incidence not known
    hepatic failure / Delayed / Incidence not known
    increased intracranial pressure / Early / Incidence not known
    suicidal ideation / Delayed / Incidence not known
    torsade de pointes / Rapid / Incidence not known
    aortic dissection / Delayed / Incidence not known
    myasthenia gravis / Delayed / Incidence not known
    C. difficile-associated diarrhea / Delayed / Incidence not known
    tendon rupture / Delayed / Incidence not known
    coma / Early / Incidence not known
    pancytopenia / Delayed / Incidence not known
    hemolytic anemia / Delayed / Incidence not known
    agranulocytosis / Delayed / Incidence not known
    aplastic anemia / Delayed / Incidence not known
    uveitis / Delayed / Incidence not known

    Moderate

    constipation / Delayed / 3.0-3.0
    photophobia / Early / 1.0-3.0
    gastritis / Delayed / 0.1-1.0
    esophagitis / Delayed / 0.1-1.0
    stomatitis / Delayed / 0.1-1.0
    glossitis / Early / 0.1-1.0
    phlebitis / Rapid / 0.1-1.0
    edema / Delayed / 1.0-1.0
    dyspnea / Early / 1.0-1.0
    elevated hepatic enzymes / Delayed / 0.1-1.0
    hallucinations / Early / 0.1-1.0
    hypertonia / Delayed / 0.1-1.0
    depression / Delayed / 0.1-1.0
    confusion / Early / 0.1-1.0
    chest pain (unspecified) / Early / 1.0-1.0
    palpitations / Early / 0.1-1.0
    pseudomembranous colitis / Delayed / 0.1-1.0
    hyperglycemia / Delayed / 0.1-1.0
    hypoglycemia / Early / 0.1-1.0
    anemia / Delayed / 0.1-1.0
    thrombocytopenia / Delayed / 0.1-1.0
    candidiasis / Delayed / 0.1-1.0
    vaginitis / Delayed / 1.0-1.0
    pneumonitis / Delayed / Incidence not known
    hepatitis / Delayed / Incidence not known
    jaundice / Delayed / Incidence not known
    memory impairment / Delayed / Incidence not known
    neurotoxicity / Early / Incidence not known
    psychosis / Early / Incidence not known
    dysphonia / Delayed / Incidence not known
    encephalopathy / Delayed / Incidence not known
    delirium / Early / Incidence not known
    pseudotumor cerebri / Delayed / Incidence not known
    peripheral vasodilation / Rapid / Incidence not known
    QT prolongation / Rapid / Incidence not known
    peripheral neuropathy / Delayed / Incidence not known
    superinfection / Delayed / Incidence not known
    tendinitis / Delayed / Incidence not known
    hypotension / Rapid / Incidence not known
    crystalluria / Delayed / Incidence not known
    prolonged bleeding time / Delayed / Incidence not known
    leukopenia / Delayed / Incidence not known
    eosinophilia / Delayed / Incidence not known
    blurred vision / Early / Incidence not known
    scotomata / Delayed / Incidence not known

    Mild

    dysgeusia / Early / 8.0-10.0
    nausea / Early / 1.0-7.0
    diarrhea / Early / 1.0-5.0
    insomnia / Early / 4.0-4.0
    fever / Early / 1.0-3.0
    dizziness / Early / 3.0-3.0
    pharyngitis / Delayed / 1.0-3.0
    ocular irritation / Rapid / 1.0-3.0
    ocular pain / Early / 1.0-3.0
    foreign body sensation / Rapid / 1.0-3.0
    abdominal pain / Early / 2.0-2.0
    vomiting / Early / 2.0-2.0
    dyspepsia / Early / 1.0-2.0
    rash / Early / 2.0-2.0
    arthralgia / Delayed / 0.1-1.0
    injection site reaction / Rapid / 1.0-1.0
    pruritus / Rapid / 1.0-1.0
    urticaria / Rapid / 0.1-1.0
    hyperkinesis / Delayed / 0.1-1.0
    anxiety / Delayed / 0.1-1.0
    vertigo / Early / 0.1-1.0
    anorexia / Delayed / 0.1-1.0
    nightmares / Early / 0.1-1.0
    syncope / Early / 0.1-1.0
    agitation / Early / 0.1-1.0
    tremor / Early / 0.1-1.0
    paresthesias / Delayed / 0.1-1.0
    myalgia / Early / 0.1-1.0
    musculoskeletal pain / Early / 0.1-1.0
    epistaxis / Delayed / 0.1-1.0
    xerophthalmia / Early / 0-1.0
    ocular pruritus / Rapid / 0-1.0
    paranoia / Early / Incidence not known
    restlessness / Early / Incidence not known
    parosmia / Delayed / Incidence not known
    anosmia / Delayed / Incidence not known
    weakness / Early / Incidence not known
    hypoesthesia / Delayed / Incidence not known
    dysesthesia / Delayed / Incidence not known
    photosensitivity / Delayed / Incidence not known
    cylindruria / Delayed / Incidence not known
    diplopia / Early / Incidence not known
    tinnitus / Delayed / Incidence not known

    DRUG INTERACTIONS

    Abarelix: (Major) Since abarelix can cause QT prolongation, abarelix should be used cautiously, if at all, with other drugs that are associated with QT prolongation including levofloxacin.
    Acarbose: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including alpha-glucosidase inhibitors, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur.
    Acetaminophen; Caffeine; Magnesium Salicylate; Phenyltoloxamine: (Moderate) Administer magnesium salicylate at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Acetohexamide: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Albiglutide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Alfuzosin: (Moderate) Use caution when administering alfuzosin with levofloxacin due to the potential for QT prolongation and torsade de pointes (TdP). Alfuzosin may prolong the QT interval in a dose-dependent manner. Additionally, levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Alogliptin: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Alogliptin; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Alogliptin; Pioglitazone: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant thiazolidinedione and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Alpha-glucosidase Inhibitors: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including alpha-glucosidase inhibitors, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur.
    Aluminum Hydroxide: (Moderate) Administer products that contain aluminum hydroxide at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids that contain aluminum hydroxide.
    Aluminum Hydroxide; Magnesium Carbonate: (Moderate) Administer magnesium carbonate at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. (Moderate) Administer products that contain aluminum hydroxide at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids that contain aluminum hydroxide.
    Aluminum Hydroxide; Magnesium Hydroxide: (Moderate) Administer magnesium hydroxide at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. (Moderate) Administer products that contain aluminum hydroxide at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids that contain aluminum hydroxide.
    Aluminum Hydroxide; Magnesium Hydroxide; Simethicone: (Moderate) Administer magnesium hydroxide at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. (Moderate) Administer products that contain aluminum hydroxide at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids that contain aluminum hydroxide.
    Aluminum Hydroxide; Magnesium Trisilicate: (Moderate) Administer products that contain aluminum hydroxide at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids that contain aluminum hydroxide. (Moderate) Administer products that contain magnesium trisilicate at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Amiodarone: (Major) Concomitant use of levofloxacin and amiodarone increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary. Due to the extremely long half-life of amiodarone, a drug interaction is possible for days to weeks after drug discontinuation.
    Amisulpride: (Major) Monitor the ECG in patients taking amisulpride with levofloxacin due to the risk of additive QT prolongation. Amisulpride causes dose- and concentration- dependent QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Amlodipine; Celecoxib: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Amoxicillin; Clarithromycin; Omeprazole: (Major) Concurrent use of clarithromycin and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Clarithromycin is also associated with an established risk for QT prolongation and TdP.
    Anagrelide: (Major) Do not use anagrelide with other drugs that prolong the QT interval. Torsade de pointes (TdP) and ventricular tachycardia have been reported with anagrelide. In addition, dose-related increases in mean QTc and heart rate were observed in healthy subjects. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Apomorphine: (Moderate) Use apomorphine and levofloxacin together with caution due to the risk of additive QT prolongation. Dose-related QTc prolongation is associated with therapeutic apomorphine exposure. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Aripiprazole: (Moderate) Levofloxacin should be used cautiously with other agents that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin. QT prolongation has occurred during therapeutic use of aripiprazole and following overdose.
    Arsenic Trioxide: (Major) Concurrent use of arsenic trioxide and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). If possible, levofloxacin should be discontinued prior to initiating arsenic trioxide therapy. Use of arsenic trioxide is expected to cause QT prolongation, and cases of TdP and complete atrioventricular block have been reported. Levofloxacin has also been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin.
    Artemether; Lumefantrine: (Major) Concurrent use of artemether; lumefantrine and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Consider ECG monitoring if levofloxacin must be used with or after artemether; lumefantrine treatment. Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. The administration of artemether; lumefantrine is also associated with prolongation of the QT interval.
    Asenapine: (Major) Concurrent use of asenapine and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Asenapine has also been associated with QT prolongation.
    Atomoxetine: (Moderate) Concomitant use of levofloxacin and atomoxetine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Azithromycin: (Major) Concomitant use of azithromycin and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Bedaquiline: (Major) Coadministration of bedaquiline with other QT prolonging drugs, such as levofloxacin, may result in additive or synergistic prolongation of the QT interval and should be avoided. Prior to initiating bedaquiline, obtain serum electrolyte concentrations and a baseline ECG. An ECG should also be performed at least 2, 12, and 24 weeks after starting bedaquiline therapy.
    Betamethasone: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Bismuth Subcitrate Potassium; Metronidazole; Tetracycline: (Moderate) Concomitant use of metronidazole and levofloxacin may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Bismuth Subsalicylate; Metronidazole; Tetracycline: (Moderate) Concomitant use of metronidazole and levofloxacin may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Budesonide: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Budesonide; Formoterol: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Budesonide; Glycopyrrolate; Formoterol: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Bupivacaine; Meloxicam: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Buprenorphine: (Major) Concomitant use of levofloxacin and buprenorphine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Buprenorphine; Naloxone: (Major) Concomitant use of levofloxacin and buprenorphine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Cabotegravir; Rilpivirine: (Moderate) Caution is advised when administering rilpivirine with levofloxacin. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Calcium Acetate: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium Carbonate: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium Carbonate; Famotidine; Magnesium Hydroxide: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium Carbonate; Magnesium Hydroxide: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium Carbonate; Magnesium Hydroxide; Simethicone: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium Carbonate; Risedronate: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium Carbonate; Simethicone: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium Chloride: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium Gluconate: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Calcium; Vitamin D: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Canagliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Canagliflozin; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Carbetapentane; Guaifenesin; Phenylephrine: (Major) Administer oral products that contain zinc at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include multivitamins that contain zinc.
    Carbetapentane; Phenylephrine: (Major) Administer oral products that contain zinc at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include multivitamins that contain zinc.
    Celecoxib: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Celecoxib; Tramadol: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Ceritinib: (Major) Avoid coadministration of ceritinib with levofloxacin if possible due to the risk of QT prolongation. If concomitant use is unavoidable, periodically monitor ECGs and electrolytes; an interruption of ceritinib therapy, dose reduction, or discontinuation of therapy may be necessary if QT prolongation occurs. Ceritinib causes concentration-dependent prolongation of the QT interval. Levofloxacin has also been associated with a risk of QT prolongation; although extremely rare, torsade de pointes (TDP) has been reported during postmarketing surveillance of levofloxacin.
    Chloroquine: (Major) Avoid coadministration of chloroquine with levofloxacin due to the increased risk of QT prolongation. If use together is necessary, obtain an ECG at baseline to assess initial QT interval and determine frequency of subsequent ECG monitoring, avoid any non-essential QT prolonging drugs, and correct electrolyte imbalances. Chloroquine is associated with an increased risk of QT prolongation and torsade de pointes (TdP); the risk of QT prolongation is increased with higher chloroquine doses. Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin.
    Chlorpheniramine; Ibuprofen; Pseudoephedrine: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Chlorpheniramine; Pseudoephedrine: (Major) Administer oral products that contain zinc at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include multivitamins that contain zinc.
    Chlorpromazine: (Major) Concurrent use of chlorpromazine and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Phenothiazines have also been associated with a risk of QT prolongation and/or TdP. This risk is generally higher at elevated drugs concentrations of phenothiazines. Chlorpromazine is specifically associated with an established risk of QT prolongation and TdP; case reports have included patients receiving therapeutic doses of chlorpromazine.
    Chlorpropamide: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Choline Salicylate; Magnesium Salicylate: (Moderate) Administer magnesium salicylate at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Chromium: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Cisapride: (Contraindicated) Avoid concomitant use of levofloxacin and cisapride due to an increased risk for torsade de pointes (TdP) and QT/QTc prolongation.
    Citalopram: (Major) Concomitant use of levofloxacin and citalopram increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Clarithromycin: (Major) Concurrent use of clarithromycin and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Clarithromycin is also associated with an established risk for QT prolongation and TdP.
    Class IA Antiarrhythmics: (Major) Levofloxacin should be avoided in combination with Class IA antiarrhythmics (disopyramide, procainamide, and quinidine). Class IA antiarrhythmics are associated with QT prolongation and torsades de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. According to the manufacturer, levofloxacin should be avoided in patients taking drugs that can result in prolongation of the QT interval.
    Clindamycin; Tretinoin: (Major) Avoid the concomitant use of tretinoin with other drugs known to cause photosensitivity, such as levofloxacin. Concomitant use with other photosensitizing agents may increase the risk of a photosensitivity reaction.
    Clofazimine: (Moderate) Concomitant use of clofazimine and levofloxacin may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Clozapine: (Moderate) Use clozapine with caution in combination with levofloxacin. Treatment with clozapine has been associated with QT prolongation, torsade de pointes (TdP), cardiac arrest, and sudden death. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Codeine; Phenylephrine; Promethazine: (Moderate) Concomitant use of levofloxacin and promethazine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Codeine; Promethazine: (Moderate) Concomitant use of levofloxacin and promethazine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Cortisone: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Crizotinib: (Major) Avoid coadministration of crizotinib with levofloxacin due to the risk of QT prolongation. If concomitant use is unavoidable, monitor ECGs for QT prolongation and monitor electrolytes. An interruption of therapy, dose reduction, or discontinuation of therapy may be necessary for crizotinib if QT prolongation occurs. Crizotinib has been associated with concentration-dependent QT prolongation. Levofloxacin has been associated with a risk of QT prolongation; although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin.
    Dapagliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Dapagliflozin; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Dapagliflozin; Saxagliptin: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Dasatinib: (Moderate) Use dasatinib with caution in combination with levofloxacin. In vitro studies have shown that dasatinib has the potential to prolong the QT interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Deflazacort: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Degarelix: (Moderate) Consider whether the benefits of androgen deprivation therapy outweigh the potential risks in patients receiving levofloxacin. Androgen deprivation therapy (i.e., degarelix) may prolong the QT/QTc interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Desogestrel; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Deutetrabenazine: (Moderate) Use levofloxacin with caution in patients receiving other drugs that prolong the QT interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin. Deutetrabenazine may prolong the QT interval, but the degree of QT prolongation is not clinically significant when deutetrabenazine is administered within the recommended dosage range.
    Dexamethasone: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Dextromethorphan; Quinidine: (Major) Levofloxacin should be avoided in combination with Class IA antiarrhythmics (disopyramide, procainamide, and quinidine). Class IA antiarrhythmics are associated with QT prolongation and torsades de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. According to the manufacturer, levofloxacin should be avoided in patients taking drugs that can result in prolongation of the QT interval.
    Diclofenac: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Diclofenac; Misoprostol: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Didanosine, ddI: (Major) Administer didanosine tablets or powder for oral solution at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as it can chelate with the buffering agents contained in didanosine tablets and powder. The delayed-release didanosine capsules do not contain a buffering agent and would not be expected to interact with levofloxacin.
    Dienogest; Estradiol valerate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Diflunisal: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Dipeptidyl Peptidase-4 Inhibitors: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Diphenhydramine; Ibuprofen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Diphenhydramine; Naproxen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Disopyramide: (Major) Levofloxacin should be avoided in combination with Class IA antiarrhythmics (disopyramide, procainamide, and quinidine). Class IA antiarrhythmics are associated with QT prolongation and torsades de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. According to the manufacturer, levofloxacin should be avoided in patients taking drugs that can result in prolongation of the QT interval.
    Dofetilide: (Major) Coadministration of dofetilide and levofloxacin is not recommended as concurrent use may increase the risk of QT prolongation. Dofetilide, a Class III antiarrhythmic agent, is associated with a well-established risk of QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Dolasetron: (Moderate) Administer dolasetron with caution in combination with levofloxacin. Dolasetron has been associated with a dose-dependent prolongation in the QT, PR, and QRS intervals on an electrocardiogram. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Dolutegravir; Rilpivirine: (Moderate) Caution is advised when administering rilpivirine with levofloxacin. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Donepezil: (Moderate) Use donepezil with caution in combination with levofloxacin. Case reports indicate that QT prolongation and torsade de pointes (TdP) can occur during donepezil therapy. Levofloxacin has also been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Donepezil; Memantine: (Moderate) Use donepezil with caution in combination with levofloxacin. Case reports indicate that QT prolongation and torsade de pointes (TdP) can occur during donepezil therapy. Levofloxacin has also been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Dronedarone: (Contraindicated) Avoid concomitant use of levofloxacin and dronedarone due to an increased risk for torsade de pointes (TdP) and QT/QTc prolongation.
    Droperidol: (Major) Droperidol should not be used in combination with any drug known to have potential to prolong the QT interval, such as levofloxacin. Droperidol administration is associated with an established risk for QT prolongation and torsade de pointes (TdP). Some cases have occurred in patients with no known risk factors for QT prolongation and some cases have been fatal. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin. If coadministration cannot be avoided, use extreme caution; initiate droperidol at a low dose and increase the dose as needed to achieve the desired effect.
    Drospirenone: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Drospirenone; Estetrol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Drospirenone; Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Drospirenone; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Drospirenone; Ethinyl Estradiol; Levomefolate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Dulaglutide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Efavirenz: (Moderate) Consider alternatives to efavirenz when coadministering with levofloxacin. QTc prolongation has been observed with the use of efavirenz. Levofloxacin has also been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Efavirenz; Emtricitabine; Tenofovir Disoproxil Fumarate: (Moderate) Consider alternatives to efavirenz when coadministering with levofloxacin. QTc prolongation has been observed with the use of efavirenz. Levofloxacin has also been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Efavirenz; Lamivudine; Tenofovir Disoproxil Fumarate: (Moderate) Consider alternatives to efavirenz when coadministering with levofloxacin. QTc prolongation has been observed with the use of efavirenz. Levofloxacin has also been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Elagolix; Estradiol; Norethindrone acetate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Eliglustat: (Moderate) Levofloxacin should be used cautiously with other agents that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Eliglustat is predicted to cause PR, QRS, and/or QT prolongation at significantly elevated plasma concentrations. Levofloxacin has also been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Empagliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Empagliflozin; Linagliptin: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Empagliflozin; Linagliptin; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Empagliflozin; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Emtricitabine; Rilpivirine; Tenofovir alafenamide: (Moderate) Caution is advised when administering rilpivirine with levofloxacin. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Emtricitabine; Rilpivirine; Tenofovir Disoproxil Fumarate: (Moderate) Caution is advised when administering rilpivirine with levofloxacin. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Encorafenib: (Major) Avoid coadministration of encorafenib and levofloxacin due to QT prolongation. If concurrent use cannot be avoided, monitor ECGs for QT prolongation and monitor electrolytes; correct hypokalemia and hypomagnesemia prior to treatment. Encorafenib is associated with dose-dependent prolongation of the QT interval. Levofloxacin has been associated with a risk of QT prolongation. Although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin.
    Enteral Feedings: (Major) Because many food products contain divalent or trivalent cations, these foods may significantly decrease the absorption of orally administered levofloxacin. Separate these foods or enteral feedings by at least 2 hours before or 2 hours after orally administered levofloxacin. Advise patients that dairy products and other high calcium- and iron-containing foods may affect the absorption of levofloxacin. The serum concentration of levofloxacin decreased by 61% when tablets were crushed and mixed with 240 mL of an enteral feeding formulation.
    Entrectinib: (Major) Avoid coadministration of entrectinib with levofloxacin due to the risk of QT prolongation. Entrectinib has been associated with QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare,TdP has been reported during postmarketing surveillance of levofloxacin.
    Eribulin: (Major) Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of torsade de pointes (TdP) have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. According to the manufacturer, levofloxacin should be avoided in patients taking drugs that can result in prolongation of the QT interval. Drugs with a possible risk for QT prolongation and TdP include eribulin. If coadministration is necessary, ECG monitoring is recommended; closely monitor the patient for QT interval prolongation.
    Ertugliflozin: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Ertugliflozin; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Ertugliflozin; Sitagliptin: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Erythromycin: (Major) Concomitant use of levofloxacin and erythromycin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Erythromycin; Sulfisoxazole: (Major) Concomitant use of levofloxacin and erythromycin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Escitalopram: (Moderate) Concomitant use of levofloxacin and escitalopram may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Estradiol; Levonorgestrel: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Estradiol; Norethindrone: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Estradiol; Norgestimate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Ethinyl Estradiol; Levonorgestrel; Folic Acid; Levomefolate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Ethinyl Estradiol; Norelgestromin: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Ethinyl Estradiol; Norethindrone Acetate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Ethinyl Estradiol; Norgestrel: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Ethynodiol Diacetate; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Etodolac: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Etonogestrel; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Exenatide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Ezogabine: (Moderate) Levofloxacin should be used cautiously with other agents, such as ezogabine, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin. Ezogabine has been associated with QT prolongation.
    Fenoprofen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Ferric Maltol: (Moderate) Administer oral products that contain iron at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Fingolimod: (Moderate) After the first fingolimod dose, overnight monitoring with continuous ECG in a medical facility is advised for patients taking QT prolonging drugs with a known risk of torsade de pointes (TdP), such as levofloxacin. Fingolimod initiation results in decreased heart rate and may prolong the QT interval. Fingolimod has not been studied in patients treated with drugs that prolong the QT interval, but drugs that prolong the QT interval have been associated with cases of TdP in patients with bradycardia. Levofloxacin has also been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Flecainide: (Major) Concomitant use of levofloxacin and flecainide increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Fluconazole: (Moderate) Concomitant use of levofloxacin and fluconazole may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Fludrocortisone: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Fluocinolone; Hydroquinone; Tretinoin: (Major) Avoid the concomitant use of tretinoin with other drugs known to cause photosensitivity, such as levofloxacin. Concomitant use with other photosensitizing agents may increase the risk of a photosensitivity reaction.
    Fluoxetine: (Moderate) Concomitant use of levofloxacin and fluoxetine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Fluphenazine: (Minor) Levofloxacin should be used cautiously with other agents, such as fluphenazine, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Fluphenazine is associated with a possible risk for QT prolongation. Theoretically, fluphenazine may increase the risk of QT prolongation if coadministered with other drugs that have a risk of QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Flurbiprofen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Fluvoxamine: (Moderate) Use fluvoxamine with caution in combination with levofloxacin. QT prolongation and torsade de pointes (TdP) have been reported during fluvoxamine and levofloxacin post-marketing use.
    Foscarnet: (Major) When possible, avoid concurrent use of foscarnet with other drugs known to prolong the QT interval, such as levofloxacin. Foscarnet has been associated with postmarketing reports of both QT prolongation and torsade de pointes (TdP). Quinolones have also been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin. If these drugs are administered together, obtain an electrocardiogram and electrolyte concentrations before and periodically during treatment.
    Fostemsavir: (Moderate) Levofloxacin should be used cautiously with other agents that may prolong the QT interval or increase the risk of TdP. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin. Supratherapeutic doses of fostemsavir (2,400 mg twice daily, four times the recommended daily dose) have been shown to cause QT prolongation. Fostemsavir causes dose-dependent QT prolongation.
    Gemtuzumab Ozogamicin: (Moderate) Use gemtuzumab ozogamicin and levofloxacin together with caution due to the potential for additive QT interval prolongation and risk of torsade de pointes (TdP). If these agents are used together, obtain an ECG and serum electrolytes prior to the start of gemtuzumab and as needed during treatment. Although QT interval prolongation has not been reported with gemtuzumab, it has been reported with other drugs that contain calicheamicin. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Gilteritinib: (Moderate) Use caution and monitor for additive QT prolongation if concurrent use of gilteritinib and levofloxacin is necessary. Gilteritinib has been associated with QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Glasdegib: (Major) Avoid coadministration of glasdegib with levofloxacin due to the potential for additive QT prolongation. If coadministration cannot be avoided, monitor patients for increased risk of QT prolongation with increased frequency of ECG monitoring. Glasdegib therapy may result in QT prolongation and ventricular arrhythmias including ventricular fibrillation and ventricular tachycardia. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin.
    Glimepiride: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Glimepiride; Rosiglitazone: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant thiazolidinedione and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Glipizide: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Glipizide; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Glyburide: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Glyburide; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Goserelin: (Moderate) Consider whether the benefits of androgen deprivation therapy outweigh the potential risks in patients receiving other QT prolonging agents, such as levofloxacin. Androgen deprivation therapy (i.e., goserelin) may prolong the QT/QTc interval. Levofloxacin has also been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Granisetron: (Moderate) Use granisetron with caution in combination with levofloxacin. Granisetron has been associated with QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Halobetasol; Tazarotene: (Moderate) Use tazarotene with caution in patients who are also taking drugs known to be photosensitizers, such as levofloxacin, due to the increased possibility of augmented phototoxicity.
    Halofantrine: (Contraindicated) Halofantrine is considered to have a well-established risk for QT prolongation and torsades de pointes and should be avoided in patients receiving drugs which may induce QT prolongation including levofloxacin.
    Halogenated Anesthetics: (Major) Halogenated anesthetics can prolong the QT interval. Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of torsade de pointes (TdP) have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. According to the manufacturer, levofloxacin should be avoided in patients taking drugs that can result in prolongation of the QT interval, such as halogenated anesthetics.
    Haloperidol: (Moderate) Caution is advisable when combining haloperidol concurrently with levofloxacin. Both drugs have been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin. Excessive doses (particularly in the overdose setting) or IV administration of haloperidol may be associated with a higher risk of QT prolongation.
    Histrelin: (Moderate) Consider whether the benefits of androgen deprivation therapy outweigh the potential risks in patients receiving other QT prolonging agents. Androgen deprivation therapy (i.e., histrelin) may prolong the QT/QTc interval. Levofloxacin has also been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Hydrocodone; Ibuprofen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Hydrocortisone: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Hydroxychloroquine: (Major) Concomitant use of hydroxychloroquine and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Hydroxyzine: (Moderate) Concomitant use of levofloxacin and hydroxyzine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Ibuprofen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Ibuprofen; Famotidine: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Ibuprofen; Oxycodone: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Ibuprofen; Pseudoephedrine: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Ibutilide: (Major) Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. According to the manufacturer, levofloxacin should be avoided in patients taking drugs that can result in prolongation of the QT interval. Ibutilide administration can cause QT prolongation and torsades de pointes (TdP); proarrhythmic events should be anticipated. The potential for proarrhythmic events with ibutilide increases with the coadministration of other drugs that prolong the QT interval.
    Iloperidone: (Major) Concurrent use of iloperidone and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Iloperidone has also been associated with QT prolongation; however, TdP has not been reported.
    Incretin Mimetics: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Indomethacin: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Inotuzumab Ozogamicin: (Major) Avoid coadministration of inotuzumab ozogamicin with levofloxacin due to the potential for additive QT prolongation and risk of torsade de pointes (TdP). If coadministration is unavoidable, obtain an ECG and serum electrolytes prior to the start of treatment, after treatment initiation, and periodically during treatment. Both inotuzumab and levofloxacin have been associated with QT prolongation. Although extremely rare, TdP has also been reported during postmarketing surveillance of levofloxacin.
    Insulin Aspart: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin Aspart; Insulin Aspart Protamine: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin Degludec: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin Degludec; Liraglutide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin Detemir: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin Glargine: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin Glargine; Lixisenatide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin Glulisine: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin Lispro: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin Lispro; Insulin Lispro Protamine: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulin, Inhaled: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Insulins: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Iron Salts: (Moderate) Administer oral products that contain iron at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Iron: (Moderate) Administer oral products that contain iron at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Isophane Insulin (NPH): (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Itraconazole: (Moderate) Use itraconazole with caution in combination with levofloxacin. Itraconazole has been associated with prolongation of the QT interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Ivosidenib: (Major) Avoid coadministration of ivosidenib with levofloxacin due to an increased risk of QT prolongation. If concomitant use is unavoidable, monitor ECGs for QTc prolongation and monitor electrolytes; correct any electrolyte abnormalities as clinically appropriate. An interruption of therapy and dose reduction of ivosidenib may be necessary if QT prolongation occurs. Prolongation of the QTc interval and ventricular arrhythmias have been reported in patients treated with ivosidenib. Levofloxacin has been associated with a risk of QT prolongation. Although extremely rare, torsade de pointes has also been reported during postmarketing surveillance of levofloxacin.
    Ketoconazole: (Contraindicated) Avoid concomitant use of ketoconazole and levofloxacin due to an increased risk for torsade de pointes (TdP) and QT/QTc prolongation. Ketoconazole is associated with QT prolongation and TdP; levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia and rare cases of TdP have been spontaneously reported during postmarketing surveillance.
    Ketoprofen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Ketorolac: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Lansoprazole; Amoxicillin; Clarithromycin: (Major) Concurrent use of clarithromycin and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Clarithromycin is also associated with an established risk for QT prolongation and TdP.
    Lansoprazole; Naproxen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Lanthanum Carbonate: (Major) Administer lanthanum carbonate at least 2 hours before or 2 hours after orally administered levofloxacin. When oral quinolones are given for short courses, consider eliminating the lanthanum carbonate doses that would be normally scheduled near the time of quinolone intake. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Lapatinib: (Moderate) Monitor for evidence of QT prolongation if lapatinib is administered with levofloxacin. Lapatinib has been associated with concentration-dependent QT prolongation; ventricular arrhythmias and torsade de pointes (TdP) have been reported in postmarketing experience with lapatinib. Levofloxacin has also been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Lefamulin: (Major) Avoid coadministration of lefamulin with levofloxacin as concurrent use may increase the risk of QT prolongation. If coadministration cannot be avoided, monitor ECG during treatment. Lefamulin has a concentration dependent QTc prolongation effect. The pharmacodynamic interaction potential to prolong the QT interval of the electrocardiogram between lefamulin and other drugs that effect cardiac conduction is unknown. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin.
    Lente Insulin: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Lenvatinib: (Major) Avoid coadministration of lenvatinib with levofloxacin due to the risk of QT prolongation. Prolongation of the QT interval has been reported with lenvatinib therapy. Levofloxacin has also been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin.
    Leuprolide: (Moderate) Consider whether the benefits of androgen deprivation therapy outweigh the potential risks in patients receiving other QT prolonging agents. Androgen deprivation therapy (i.e., leuprolide) may prolong the QT/QTc interval. Levofloxacin has also been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Leuprolide; Norethindrone: (Moderate) Consider whether the benefits of androgen deprivation therapy outweigh the potential risks in patients receiving other QT prolonging agents. Androgen deprivation therapy (i.e., leuprolide) may prolong the QT/QTc interval. Levofloxacin has also been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin. (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Levoketoconazole: (Contraindicated) Avoid concomitant use of ketoconazole and levofloxacin due to an increased risk for torsade de pointes (TdP) and QT/QTc prolongation. Ketoconazole is associated with QT prolongation and TdP; levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia and rare cases of TdP have been spontaneously reported during postmarketing surveillance.
    Levonorgestrel: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Levonorgestrel; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Levonorgestrel; Ethinyl Estradiol; Ferrous Bisglycinate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Linagliptin: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Linagliptin; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Liraglutide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Lithium: (Moderate) Concomitant use of levofloxacin and lithium may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Lixisenatide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Lofexidine: (Major) Monitor ECG if lofexidine is coadministered with levofloxacin due to the potential for additive QT prolongation and torsade de pointes (TdP). Lofexidine prolongs the QT interval. In addition, there are postmarketing reports of TdP. Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported with levofloxacin during postmarketing surveillance.
    Loperamide: (Moderate) Concomitant use of levofloxacin and loperamide may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Loperamide; Simethicone: (Moderate) Concomitant use of levofloxacin and loperamide may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Lopinavir; Ritonavir: (Major) Avoid coadministration of lopinavir with levofloxacin due to the potential for additive QT prolongation. If use together is necessary, obtain a baseline ECG to assess initial QT interval and determine frequency of subsequent ECG monitoring, avoid any non-essential QT prolonging drugs, and correct electrolyte imbalances. Lopinavir is associated with QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin.
    Macimorelin: (Major) Avoid concurrent administration of macimorelin with drugs that prolong the QT interval, such as levofloxacin. Use of these drugs together may increase the risk of developing torsade de pointes-type ventricular tachycardia. Sufficient washout time of drugs that are known to prolong the QT interval prior to administration of macimorelin is recommended. Treatment with macimorelin has been associated with an increase in the corrected QT (QTc) interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, torsade de pointes have been reported during postmarketing surveillance of levofloxacin.
    Magnesium Citrate: (Moderate) Administer magnesium citrate at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Magnesium Hydroxide: (Moderate) Administer magnesium hydroxide at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Magnesium Salicylate: (Moderate) Administer magnesium salicylate at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Magnesium Sulfate; Potassium Sulfate; Sodium Sulfate: (Major) Administer quinolones at least 2 hours before or 6 hours after administration of magnesium sulfate; potassium sulfate; sodium sulfate. The absorption of quinolones may be reduced by chelation with magnesium sulfate.
    Magnesium: (Moderate) Administer oral products that contain magnesium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Maprotiline: (Moderate) Levofloxacin should be used cautiously with other agents, such as maprotiline, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Maprotiline has been reported to prolong the QT interval, particularly in overdose or with higher-dose prescription therapy (elevated serum concentrations). Cases of long QT syndrome and TdP tachycardia have been described with maprotiline use, but rarely occur when the drug is used alone in normal prescribed doses and in the absence of other known risk factors for QT prolongation. Limited data are available regarding the safety of maprotiline in combination with other QT-prolonging drugs. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Meclofenamate Sodium: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Mefenamic Acid: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Mefloquine: (Moderate) Mefloquine should be used with caution in patients receiving levofloxacin. There is evidence that the use of halofantrine after mefloquine causes a significant lengthening of the QTc interval. Mefloquine alone has not been reported to cause QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Meglitinides: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including meglitinides, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur.
    Meloxicam: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Meperidine; Promethazine: (Moderate) Concomitant use of levofloxacin and promethazine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Mequinol; Tretinoin: (Major) Avoid the concomitant use of tretinoin with other drugs known to cause photosensitivity, such as levofloxacin. Concomitant use with other photosensitizing agents may increase the risk of a photosensitivity reaction.
    Mestranol; Norethindrone: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur.
    Metformin; Repaglinide: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including meglitinides, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur.
    Metformin; Rosiglitazone: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant thiazolidinedione and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Metformin; Saxagliptin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Metformin; Sitagliptin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Methadone: (Major) Concurrent use of methadone and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Methadone is also considered to be associated with an increased risk for QT prolongation and TdP, especially at higher doses (> 200 mg/day but averaging approximately 400 mg/day). Laboratory studies, both in vivo and in vitro, have demonstrated that methadone inhibits cardiac potassium channels and prolongs the QT interval. Most cases involve patients being treated for pain with large, multiple daily doses of methadone, although cases have been reported in patients receiving doses commonly used for maintenance treatment of opioid addiction.
    Methylprednisolone: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Metronidazole: (Moderate) Concomitant use of metronidazole and levofloxacin may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Midostaurin: (Major) The concomitant use of midostaurin and levofloxacin may lead to additive QT interval prolongation. If these drugs are used together, consider electrocardiogram monitoring. In clinical trials, QT prolongation has been reported in patients who received midostaurin as single-agent therapy or in combination with cytarabine and daunorubicin. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Mifepristone: (Major) Concomitant use of levofloxacin and mifepristone increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Miglitol: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including alpha-glucosidase inhibitors, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur.
    Mirtazapine: (Moderate) Concomitant use of levofloxacin and mirtazapine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Mobocertinib: (Major) Concomitant use of mobocertinib and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Nabumetone: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Naproxen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Naproxen; Esomeprazole: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Naproxen; Pseudoephedrine: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Nateglinide: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including meglitinides, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur.
    Nilotinib: (Major) Avoid the concomitant use of nilotinib and levofloxacin; significant prolongation of the QT interval may occur. Sudden death and QT prolongation have been reported in patients who received nilotinib therapy. Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of torsade de pointes have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin.
    Nonsteroidal antiinflammatory drugs: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Norethindrone Acetate; Ethinyl Estradiol; Ferrous fumarate: (Moderate) Administer oral products that contain iron at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Norethindrone: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Norethindrone; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Norethindrone; Ethinyl Estradiol; Ferrous fumarate: (Moderate) Administer oral products that contain iron at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Norgestimate; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Norgestrel: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Octreotide: (Moderate) Use octreotide with caution in combination with levofloxacin. Arrhythmias, sinus bradycardia, and conduction disturbances have occurred during octreotide therapy. Since bradycardia is a risk factor for development of torsade de pointes (TdP), the potential occurrence of bradycardia during octreotide administration could theoretically increase the risk of TdP in patients receiving drugs that prolong the QT interval. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Olanzapine: (Moderate) Caution is advised when administering olanzapine with levofloxacin. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Olanzapine; Fluoxetine: (Moderate) Caution is advised when administering olanzapine with levofloxacin. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin. (Moderate) Concomitant use of levofloxacin and fluoxetine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Olanzapine; Samidorphan: (Moderate) Caution is advised when administering olanzapine with levofloxacin. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Ondansetron: (Major) Concomitant use of ondansetron and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Oral Contraceptives: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Osilodrostat: (Moderate) Monitor ECGs in patients receiving osilodrostat with levofloxacin. Osilodrostat is associated with dose-dependent QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Osimertinib: (Major) Avoid coadministration of levofloxacin with osimertinib if possible due to the risk of QT prolongation and torsade de pointes (TdP). If concomitant use is unavoidable, periodically monitor ECGs for QT prolongation and monitor electrolytes; an interruption of osimertinib therapy with dose reduction or discontinuation of therapy may be necessary if QT prolongation occurs. Concentration-dependent QTc prolongation occurred during clinical trials of osimertinib. Levofloxacin has been associated with a risk of QT prolongation; although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Oxaliplatin: (Major) Monitor electrolytes and ECGs for QT prolongation if coadministration of levofloxacin with oxaliplatin is necessary; correct electrolyte abnormalities prior to administration of oxaliplatin. Levofloxacin has been associated with a risk of QT prolongation and, although extremely rare, torsade de pointes (TdP) has been reported during postmarketing surveillance of levofloxacin. QT prolongation and ventricular arrhythmias including fatal TdP have also been reported with oxaliplatin use in postmarketing experience.
    Oxaprozin: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Ozanimod: (Major) In general, do not initiate ozanimod in patients taking levofloxacin due to the risk of additive bradycardia, QT prolongation, and torsade de pointes (TdP). If treatment initiation is considered, seek advice from a cardiologist. Ozanimod initiation may result in a transient decrease in heart rate and atrioventricular conduction delays. Ozanimod has not been studied in patients taking concurrent QT prolonging drugs; however, QT prolonging drugs have been associated with TdP in patients with bradycardia. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Pacritinib: (Major) Concomitant use of pacritinib and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Paliperidone: (Major) Concurrent use of paliperidone and levofloxacin should be avoided if possible due to an increased risk for QT prolongation and torsade de pointes (TdP). If coadministration is necessary and the patient has known risk factors for cardiac disease or arrhythmias, close monitoring is essential. Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmias. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Paliperidone has also been associated with QT prolongation; TdP and ventricular fibrillation have been reported in the setting of overdose.
    Panobinostat: (Major) QT prolongation has been reported with panobinostat therapy in patients with multiple myeloma in a clinical trial; use of panobinostat with other agents that prolong the QT interval is not recommended. Obtain an electrocardiogram at baseline and periodically during treatment. Hold panobinostat if the QTcF increases to >= 480 milliseconds during therapy; permanently discontinue if QT prolongation does not resolve. Drugs with a possible risk for QT prolongation and torsade de pointes that should be used cautiously and with close monitoring with panobinostat include levofloxacin.
    Pasireotide: (Moderate) Use caution when using pasireotide in combination with other drugs, such as levofloxacin, that prolong the QT interval. QT prolongation has occurred with pasireotide at therapeutic and supra-therapeutic doses. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Pazopanib: (Major) Concurrent use of pazopanib and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). If these drugs must be continued, closely monitor the patient for QT interval prolongation. Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Pazopanib has also been reported to prolong the QT interval.
    Pentamidine: (Major) Concurrent use of pentamidine and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Pentamidine has also been associated with QT prolongation.
    Perphenazine: (Minor) Levofloxacin should be used cautiously with other agents, such as perphenazine, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Perphenazine is associated with a possible risk for QT prolongation. Theoretically, perphenazine may increase the risk of QT prolongation if coadministered with other drugs that have a risk of QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Perphenazine; Amitriptyline: (Minor) Levofloxacin should be used cautiously with other agents, such as perphenazine, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Perphenazine is associated with a possible risk for QT prolongation. Theoretically, perphenazine may increase the risk of QT prolongation if coadministered with other drugs that have a risk of QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Pimavanserin: (Major) Pimavanserin may cause QT prolongation and should generally be avoided in patients receiving other medications known to prolong the QT interval, such as levofloxacin. Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of torsade de pointes (TdP) have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Coadministration may increase the risk for QT prolongation.
    Pimozide: (Contraindicated) Avoid concomitant use of pimozide and levofloxacin due to an increased risk for torsade de pointes (TdP) and QT/QTc prolongation.
    Pioglitazone: (Moderate) Monitor blood glucose during concomitant thiazolidinedione and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Pioglitazone; Glimepiride: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia. (Moderate) Monitor blood glucose during concomitant thiazolidinedione and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Pioglitazone; Metformin: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including metformin, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur. (Moderate) Monitor blood glucose during concomitant thiazolidinedione and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Piroxicam: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Pitolisant: (Major) Avoid coadministration of pitolisant with levofloxacin as concurrent use may increase the risk of QT prolongation. Pitolisant prolongs the QT interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin.
    Polycarbophil: (Major) Administer calcium polycarbophil at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Polyethylene Glycol; Electrolytes: (Major) Administer quinolones at least 2 hours before or 6 hours after administration of magnesium sulfate; potassium sulfate; sodium sulfate. The absorption of quinolones may be reduced by chelation with magnesium sulfate.
    Polyethylene Glycol; Electrolytes; Ascorbic Acid: (Major) Administer quinolones at least 2 hours before or 6 hours after administration of magnesium sulfate; potassium sulfate; sodium sulfate. The absorption of quinolones may be reduced by chelation with magnesium sulfate.
    Polysaccharide-Iron Complex: (Moderate) Administer oral products that contain iron at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Ponesimod: (Major) In general, do not initiate ponesimod in patients taking levofloxacin due to the risk of additive bradycardia, QT prolongation, and torsade de pointes (TdP). If treatment initiation is considered, seek advice from a cardiologist. Ponesimod initiation may result in a transient decrease in heart rate and atrioventricular conduction delays. Ponesimod has not been studied in patients taking concurrent QT prolonging drugs; however, QT prolonging drugs have been associated with TdP in patients with bradycardia. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Porfimer: (Major) Avoid the concomitant use of porfimer with other drugs known to cause photosensitivity, such as levofloxacin. Concomitant use with other photosensitizing agents may increase the risk of a photosensitivity reaction.
    Posaconazole: (Moderate) Use posaconazole with caution in combination with levofloxacin. Posaconazole has been associated with prolongation of the QT interval as well as rare cases of torsade de pointes (TdP). Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Pramlintide: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including pramlintide, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur.
    Prednisolone: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Prednisone: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Primaquine: (Moderate) Levofloxacin should be used cautiously with other agents, such as primaquine, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Primaquine has the potential to prolong the QT interval. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Procainamide: (Major) Levofloxacin should be avoided in combination with Class IA antiarrhythmics (disopyramide, procainamide, and quinidine). Class IA antiarrhythmics are associated with QT prolongation and torsades de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. According to the manufacturer, levofloxacin should be avoided in patients taking drugs that can result in prolongation of the QT interval.
    Prochlorperazine: (Minor) Levofloxacin should be used cautiously with other agents, such as prochlorperazine, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Prochlorperazine is associated with a possible risk for QT prolongation. Theoretically, prochlorperazine may increase the risk of QT prolongation if coadministered with other drugs that have a risk of QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Promethazine: (Moderate) Concomitant use of levofloxacin and promethazine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Promethazine; Dextromethorphan: (Moderate) Concomitant use of levofloxacin and promethazine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Promethazine; Phenylephrine: (Moderate) Concomitant use of levofloxacin and promethazine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Propafenone: (Major) Concomitant use of levofloxacin and propafenone increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Pyridoxine, Vitamin B6: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
    Quetiapine: (Major) Concomitant use of levofloxacin and quetiapine increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Quinapril: (Moderate) Administer quinapril tablets, which contain magnesium, at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Quinapril; Hydrochlorothiazide, HCTZ: (Moderate) Administer quinapril tablets, which contain magnesium, at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Quinidine: (Major) Levofloxacin should be avoided in combination with Class IA antiarrhythmics (disopyramide, procainamide, and quinidine). Class IA antiarrhythmics are associated with QT prolongation and torsades de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. According to the manufacturer, levofloxacin should be avoided in patients taking drugs that can result in prolongation of the QT interval.
    Quinine: (Major) Concurrent use of quinine and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Quinine has been associated with prolongation of the QT interval and rare cases of TdP. Levofloxacin has also been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin.
    Ranolazine: (Moderate) Levofloxacin should be used cautiously with other agents, such as ranolazine, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin. Ranolazine is associated with dose- and plasma concentration-related increases in the QTc interval. Although there are no studies examining the effects of ranolazine in patients receiving other QT prolonging drugs, coadministration of such drugs may result in additive QT prolongation.
    Regular Insulin: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Regular Insulin; Isophane Insulin (NPH): (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Relugolix: (Moderate) Levofloxacin should be used cautiously with other agents that may prolong the QT interval such as relugolix. Levofloxacin has been associated with a risk of QT prolongation; although extremely rare, torsade de pointes (TdP) has also been reported during postmarketing surveillance. Androgen deprivation therapy (i.e., relugolix) may also prolong the QT/QTc interval.
    Relugolix; Estradiol; Norethindrone acetate: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available. (Moderate) Levofloxacin should be used cautiously with other agents that may prolong the QT interval such as relugolix. Levofloxacin has been associated with a risk of QT prolongation; although extremely rare, torsade de pointes (TdP) has also been reported during postmarketing surveillance. Androgen deprivation therapy (i.e., relugolix) may also prolong the QT/QTc interval.
    Repaglinide: (Moderate) Monitor blood glucose carefully when systemic quinolones and antidiabetic agents, including meglitinides, are coadministered. Discontinue the quinolone if a hypoglycemic reaction occurs and initiate appropriate therapy immediately. Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with quinolones and an antidiabetic agent. Hypoglycemia, sometimes resulting in coma, can occur.
    Ribociclib: (Major) Avoid coadministration of ribociclib with levofloxacin due to an increased risk for QT prolongation and torsade de pointes (TdP). Ribociclib has been shown to prolong the QT interval in a concentration-dependent manner. Levofloxacin has also been associated with a risk of QT prolongation and although extremely rare, TdP has been reported during postmarketing surveillance. Concomitant use may increase the risk for QT prolongation.
    Ribociclib; Letrozole: (Major) Avoid coadministration of ribociclib with levofloxacin due to an increased risk for QT prolongation and torsade de pointes (TdP). Ribociclib has been shown to prolong the QT interval in a concentration-dependent manner. Levofloxacin has also been associated with a risk of QT prolongation and although extremely rare, TdP has been reported during postmarketing surveillance. Concomitant use may increase the risk for QT prolongation.
    Rilpivirine: (Moderate) Caution is advised when administering rilpivirine with levofloxacin. Supratherapeutic doses of rilpivirine (75 to 300 mg/day) have caused QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Risperidone: (Moderate) Use risperidone and levofloxacin together with caution due to the potential for additive QT prolongation and risk of torsade de pointes (TdP). Risperidone has been associated with a possible risk for QT prolongation and/or TdP, primarily in the overdose setting. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin.
    Rofecoxib: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Romidepsin: (Moderate) Consider monitoring electrolytes and ECGs at baseline and periodically during treatment if romidepsin is administered with levofloxacin. Romidepsin has been reported to prolong the QT interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Rosiglitazone: (Moderate) Monitor blood glucose during concomitant thiazolidinedione and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Saquinavir: (Major) Concurrent use of saquinavir and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). If no acceptable alternative therapy is available, perform a baseline ECG prior to initiation of concomitant therapy and carefully follow monitoring recommendations. Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Saquinavir boosted with ritonavir increases the QT interval in a dose-dependent fashion, which may increase the risk for serious arrhythmias such as TdP.
    Saxagliptin: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Segesterone Acetate; Ethinyl Estradiol: (Moderate) It would be prudent to recommend alternative or additional contraception when oral contraceptives (OCs) are used in conjunction with antibiotics. It was previously thought that antibiotics may decrease the effectiveness of OCs containing estrogens due to stimulation of metabolism or a reduction in enterohepatic circulation via changes in GI flora. One retrospective study reviewed the literature to determine the effects of oral antibiotics on the pharmacokinetics of contraceptive estrogens and progestins, and also examined clinical studies in which the incidence of pregnancy with OCs and antibiotics was reported. It was concluded that the antibiotics ampicillin, ciprofloxacin, clarithromycin, doxycycline, metronidazole, ofloxacin, roxithromycin, temafloxacin, and tetracycline did not alter plasma concentrations of OCs. Antituberculous drugs (e.g., rifampin) were the only agents associated with OC failure and pregnancy. Based on the study results, these authors recommended that back-up contraception may not be necessary if OCs are used reliably during oral antibiotic use. Another review concurred with these data, but noted that individual patients have been identified who experienced significant decreases in plasma concentrations of combined OC components and who appeared to ovulate; the agents most often associated with these changes were rifampin, tetracyclines, and penicillin derivatives. These authors concluded that because females most at risk for OC failure or noncompliance may not be easily identified and the true incidence of such events may be under-reported, and given the serious consequence of unwanted pregnancy, that recommending an additional method of contraception during short-term antibiotic use may be justified. During long-term antibiotic administration, the risk for drug interaction with OCs is less clear, but alternative or additional contraception may be advisable in selected circumstances. Data regarding progestin-only contraceptives or for newer combined contraceptive deliveries (e.g., patches, rings) are not available.
    Selpercatinib: (Major) Monitor ECGs more frequently for QT prolongation if coadministration of selpercatinib with levofloxacin is necessary due to the risk of additive QT prolongation. Concentration-dependent QT prolongation has been observed with selpercatinib therapy. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, torsade de pointes has been reported during postmarketing surveillance of levofloxacin.
    Semaglutide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Sertraline: (Moderate) Concomitant use of levofloxacin and sertraline may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP. The degree of QT prolongation associated with sertraline is not clinically significant when administered within the recommended dosage range; QT prolongation has been described at 2 times the maximum recommended dose.
    Sevelamer: (Major) Administer sevelamer at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    SGLT2 Inhibitors: (Moderate) Monitor blood glucose during concomitant SGLT2 inhibitor and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Simvastatin; Sitagliptin: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Siponimod: (Major) In general, do not initiate treatment with siponimod in patients receiving levofloxacin due to the potential for QT prolongation. Consult a cardiologist regarding appropriate monitoring if siponimod use is required. Siponimod therapy prolonged the QT interval at recommended doses in a clinical study. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Sitagliptin: (Moderate) Monitor blood glucose during concomitant dipeptidyl peptidase-4 inhibitors and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Sodium Ferric Gluconate Complex; ferric pyrophosphate citrate: (Moderate) Administer oral products that contain iron at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Sodium picosulfate; Magnesium oxide; Anhydrous citric acid: (Major) Prior or concomitant use of antibiotics with sodium picosulfate; magnesium oxide; anhydrous citric acid may reduce efficacy of the bowel preparation as conversion of sodium picosulfate to its active metabolite bis-(p-hydroxy-phenyl)-pyridyl-2-methane (BHPM) is mediated by colonic bacteria. If possible, avoid coadministration. Certain antibiotics (i.e., tetracyclines and quinolones) may chelate with the magnesium in sodium picosulfate; magnesium oxide; anhydrous citric acid solution. Therefore, these antibiotics should be taken at least 2 hours before and not less than 6 hours after the administration of sodium picosulfate; magnesium oxide; anhydrous citric acid solution.
    Sodium Stibogluconate: (Moderate) Concomitant use of sodium stibogluconate and levofloxacin may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Solifenacin: (Moderate) Levofloxacin should be used cautiously with solifenacin as concurrent use may increase the risk for QT prolongation. Solifenacin has been associated with dose-dependent prolongation of the QT interval. TdP has been reported with postmarketing use, although causality was not determined. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Sorafenib: (Major) Avoid coadministration of sorafenib with levofloxacin due to the risk of additive QT prolongation. If concomitant use is unavoidable, monitor electrocardiograms and correct electrolyte abnormalities. An interruption or discontinuation of sorafenib therapy may be necessary if QT prolongation occurs. Sorafenib is associated with QTc prolongation. Levofloxacin has been associated with a risk of QT prolongation; although extremely rare, torsade de pointes (TdP) has been reported during postmarketing surveillance of levofloxacin.
    Sotalol: (Major) Concomitant use of levofloxacin and sotalol increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    St. John's Wort, Hypericum perforatum: (Moderate) Use St. John's Wort with caution in patients who are also taking drugs known to be photosensitizers, such as levofloxacin, due to the increased possibility of augmented phototoxicity.
    Sucralfate: (Moderate) Administer sucralfate at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with sucralfate. This interaction appears to be the result of chelation by the aluminum content of sucralfate. Chelation of divalent cations with levofloxacin is less than with other quinolones.
    Sulfonylureas: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Sulindac: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Sumatriptan; Naproxen: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Sunitinib: (Moderate) Monitor for evidence of QT prolongation if sunitinib is administered with levofloxacin. Sunitinib can prolong the QT interval. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Tacrolimus: (Moderate) Consider ECG and electrolyte monitoring periodically during treatment if tacrolimus is administered with levofloxacin. Tacrolimus may prolong the QT interval and cause torsade de pointes (TdP). Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Tamoxifen: (Moderate) Concomitant use of tamoxifen and levofloxacin may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Tazarotene: (Moderate) Use tazarotene with caution in patients who are also taking drugs known to be photosensitizers, such as levofloxacin, due to the increased possibility of augmented phototoxicity.
    Telavancin: (Moderate) Use caution if telavancin is administered with levofloxacin. Telavancin has been associated with QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Telithromycin: (Moderate) Levofloxacin should be used cautiously with telithromycin as concurrent use may increase the risk for QT prolongation. Telithromycin and levofloxacin have been associated with QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Tetrabenazine: (Major) Concomitant use of tetrabenazine and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Thiazolidinediones: (Moderate) Monitor blood glucose during concomitant thiazolidinedione and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Thioridazine: (Contraindicated) Avoid concomitant use of thioridazine and levofloxazin due to an increased risk for torsade de pointes (TdP) and QT/QTc prolongation.
    Tirzepatide: (Moderate) Monitor blood glucose during concomitant incretin mimetic and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Tolazamide: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Tolbutamide: (Moderate) Monitor blood glucose during concomitant sulfonylurea and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Tolmetin: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Tolterodine: (Moderate) Levofloxacin should be used cautiously with tolterodine as concurrent use may increase the risk for QT prolongation. Tolterodine has been associated with dose-dependent prolongation of the QT interval, especially in poor CYP2D6 metabolizers. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, torsade de pointes (TdP) has been reported during postmarketing surveillance of levofloxacin.
    Toremifene: (Major) Concomitant use of toremifene and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Trazodone: (Major) Concomitant use of levofloxacin and trazodone increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Tretinoin, ATRA: (Major) Avoid the concomitant use of tretinoin with other drugs known to cause photosensitivity, such as levofloxacin. Concomitant use with other photosensitizing agents may increase the risk of a photosensitivity reaction.
    Tretinoin; Benzoyl Peroxide: (Major) Avoid the concomitant use of tretinoin with other drugs known to cause photosensitivity, such as levofloxacin. Concomitant use with other photosensitizing agents may increase the risk of a photosensitivity reaction.
    Triamcinolone: (Moderate) Quinolones have been associated with an increased risk of tendon rupture requiring surgical repair or resulting in prolonged disability; this risk is further increased in those receiving concomitant corticosteroids. Discontinue quinolone therapy at the first sign of tendon inflammation or tendon pain, as these are symptoms that may precede rupture of the tendon.
    Triclabendazole: (Moderate) Concomitant use of triclabendazole and levofloxacin may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Trifluoperazine: (Minor) Levofloxacin should be used cautiously with other agents, such as trifluoperazine, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Trifluoperazine is associated with a possible risk for QT prolongation. Theoretically, trifluoperazine may increase the risk of QT prolongation if coadministered with other drugs that have a risk of QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Triptorelin: (Moderate) Consider whether the benefits of androgen deprivation therapy outweigh the potential risks in patients receiving levofloxacin as concurrent use may increase the risk for QT prolongation. Androgen deprivation therapy (i.e., triptorelin) may prolong the QT/QTc interval. Levofloxacin has also been associated with a risk of QT prolongation and torsade de pointes (TdP). Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Ultralente Insulin: (Moderate) Monitor blood glucose during concomitant insulin and quinolone use. Concomitant use may cause an increased blood glucose-lowering effect with risk of hypoglycemia.
    Valdecoxib: (Moderate) Use quinolones and nonsteroidal anti-inflammatory drugs (NSAIDs) concomitantly with caution due to potential increased risk of CNS stimulation and convulsive seizures. NSAIDs in combination with very high doses of quinolones have been shown to provoke convulsions in preclinical studies and postmarketing.
    Vandetanib: (Major) Concomitant use of vandetanib and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Vardenafil: (Moderate) Concomitant use of levofloxacin and vardenafil may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Vemurafenib: (Major) Concomitant use of vemurafenib and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.
    Venlafaxine: (Moderate) Concomitant use of levofloxacin and venlafaxine may increase the risk of QT/QTc prolongation and torsade de pointes (TdP) in some patients. Consider taking steps to minimize the risk of QT/QTc interval prolongation and TdP, such as avoidance, electrolyte monitoring and repletion, and ECG monitoring, especially in patients with additional risk factors for TdP.
    Verteporfin: (Moderate) Concomitant use of verteporfin with other photosensitizing agents, such as levofloxacin, may increase the potential for skin photosensitivity reactions.
    Voclosporin: (Moderate) Concomitant use of voclosporin and levofloxacin may increase the risk of QT prolongation. Consider interventions to minimize the risk of progression to torsades de pointes (TdP), such as ECG monitoring and correcting electrolyte abnormalities, particularly in patients with additional risk factors for TdP. Voclosporin has been associated with QT prolongation at supratherapeutic doses. Levofloxacin has been associated with a risk of QT prolongation. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Vonoprazan; Amoxicillin; Clarithromycin: (Major) Concurrent use of clarithromycin and levofloxacin should be avoided due to an increased risk for QT prolongation and torsade de pointes (TdP). Levofloxacin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Additionally, rare cases of TdP have been spontaneously reported during postmarketing surveillance in patients receiving levofloxacin. Clarithromycin is also associated with an established risk for QT prolongation and TdP.
    Voriconazole: (Moderate) Levofloxacin should be used cautiously with other agents, such as voriconazole, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Voriconazole and levofloxacin have been associated with QT prolongation and rare cases of TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Vorinostat: (Moderate) Levofloxacin should be used cautiously with other agents, such as vorinostat, that may prolong the QT interval or increase the risk of torsade de pointes (TdP). Vorinostat therapy is associated with a risk of QT prolongation. Levofloxacin has been associated with a risk of QT prolongation and TdP. Although extremely rare, TdP has been reported during postmarketing surveillance of levofloxacin.
    Warfarin: (Moderate) Closely monitor the INR and for evidence of bleeding if levofloxacin is administered concomitantly with warfarin. There have been postmarketing reports that levofloxacin enhances the effects of warfarin. Elevations of prothrombin time in the setting of concomitant levofloxacin and warfarin use have been associated with episodes of bleeding.
    Zinc Salts: (Major) Administer oral products that contain zinc at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include multivitamins that contain zinc.
    Zinc: (Major) Administer oral products that contain zinc at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include multivitamins that contain zinc.
    Ziprasidone: (Major) Concomitant use of ziprasidone and levofloxacin increases the risk of QT/QTc prolongation and torsade de pointes (TdP). Avoid concomitant use if possible, especially in patients with additional risk factors for TdP. Consider taking steps to minimize the risk for QT/QTc interval prolongation and TdP, such as electrolyte monitoring and repletion and ECG monitoring, if concomitant use is necessary.

    PREGNANCY AND LACTATION

    Pregnancy

    Published information on levofloxacin administration during pregnancy have not identified any drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes.  In a nested, case-control study (n = 87,020 controls; 8,702 cases) within the Quebec Pregnancy Cohort, quinolone use during early pregnancy was associated with an increased risk of spontaneous abortion (adjusted odds ratio (aOR) 2.72; 95% CI: 2.27 to 3.27; 160 exposed cases); residual confounding by severity of infection may be a potential limitation of this study.[62176] In a large population-based cohort study (n = 139,938 live births) assessing antibiotic exposure during the first trimester of pregnancy (n = 15,469 exposures) and the risk of major birth defects, quinolone use was associated with an increased risk of urinary system malformations (aOR 1.89; 95% CI: 1.09 to 3.28, 14 exposed cases).[62177]

    Levofloxacin is present in human breast milk after systemic administration. There is no information regarding the effects of levofloxacin on milk production or the breast-fed infant. Because of the potential risks of serious adverse reactions in breast-fed infants, breast-feeding is not recommended during treatment with levofloxacin and for an additional 2 days (5 half-lives) after the last dose. A lactating woman may consider pumping and discarding breast milk during treatment with levofloxacin and for an additional 2 days after the last dose.[63729] [65562] During an incident resulting in exposure to anthrax, the risk-benefit assessment of continuing breast-feeding while the mother is receiving levofloxacin may be acceptable; consider the developmental and health benefits of breast-feeding along with the mother's clinical need for levofloxacin and any potential adverse effects on the breast-fed child from levofloxacin or the underlying maternal condition.[28421] In a single case report, the peak levofloxacin breast milk concentration in a woman receiving 500 mg IV was 8.2 mcg/mL at 5 hours after the dose. The estimated maximum daily dose of levofloxacin through breast-feeding that an infant fed exclusively with breast milk (approximately 900 mL/day) would receive is 5 mg (approximately 1% of the maternal daily dose).[63729] [65562] Ciprofloxacin, sulfamethoxazole; trimethoprim, ceftazidime, ceftriaxone, cefepime, and piperacillin; tazobactam may be potential systemic alternatives to consider during breast-feeding. However, site of infection, patient factors, local susceptibility patterns, and specific microbial susceptibility should be assessed before choosing an alternative agent.[27500] Other beta-lactams, such as cefepime and piperacillin; tazobactam are generally considered compatible with breast-feeding.[46945] [46946] [46947] Use caution when administering the levofloxacin ophthalmic solution to a breast-feeding mother; however, the systemic absorption after topical ocular administration is minimal and would not be expected to result in clinically significant breast milk concentrations.[40311]

    MECHANISM OF ACTION

    Levofloxacin is bactericidal via inhibition of DNA gyrase (topoisomerase II), an enzyme responsible for counteracting the excessive supercoiling of DNA during replication or transcription and topoisomerase IV, an enzyme that helps separate the daughter DNA molecules. In gram-negative bacteria, the primary target is the DNA gyrase A subunit, while the primary target in gram-positive bacteria is generally topoisomerase IV. Levofloxacin exhibits concentration-dependent pharmacodynamics where the ratio of area under the concentration curve of free drug to minimal inhibitory concentration (free AUC:MIC) appears to best correlate with antibacterial activity. Additionally, levofloxacin and other quinolones exhibit a prolonged post-antibiotic effect (PAE) for gram-negative organisms. [34143] [55080] [55081]
     
    The susceptibility interpretive criteria for levofloxacin are delineated by pathogen. The MICs are defined for S. pneumoniae, beta-hemolytic streptococci, Enterococcus sp., S. viridans group, Acinetobacter sp., B. cepacia complex, S. maltophilia, and other non-Enterobacterales as susceptible at 2 mcg/mL or less, intermediate at 4 mcg/mL, and resistant at 8 mcg/mL or more. The MICs are defined for P. aeruginosa as susceptible at 1 mcg/mL or less, intermediate at 2 mcg/mL, and resistant at 4 mcg/mL or more (based on a dosage of 750 mg every 24 hours). The MICs are defined for Enterobacterales (except Salmonella sp.) as susceptible at 0.5 mcg/mL or less, intermediate at 1 mcg/mL, and resistant at 2 mcg/mL or more (based on a dosage of 750 mg every 24 hours). The MICs are defined for Salmonella sp. as susceptible at 0.12 mcg/mL or less, intermediate at 0.25 to 1 mcg/mL, and resistant at 2 mcg/mL or more. The Clinical and Laboratory Standards Institute (CLSI) and the FDA differ on MIC interpretation for Staphylococcus sp. The MICs are defined for MSSA by the FDA as susceptible at 2 mcg/mL or less, intermediate at 4 mcg/mL, and resistant at 8 mcg/mL or more; however the MICs are defined for Staphylococcus sp. by CLSI as susceptible at 1 mcg/mL or less, intermediate at 2 mcg/mL, and resistant at 4 mcg/mL or more. The MICs are defined for H. influenzae or H. parainfluenzae as susceptible at 2 mcg/mL or less. The MICs are defined for N. meningitidis as susceptible at 0.03 mcg/mL or less, intermediate at 0.06 mcg/mL, and resistant at 0.12 mcg/mL or more.[63320] [63321]
     
    Resistance to quinolones, including levofloxacin, can occur due to multiple-step mutations in defined regions of the target bacterial enzymes topoisomerase IV and DNA gyrase, referred to as Quinolone-Resistance Determining Regions (QRDRs), or through altered efflux.[34162] [49843] [63728]

    PHARMACOKINETICS

    Levofloxacin can be administered orally, intravenously, or ophthalmically. Levofloxacin is about 24% to 38% bound to serum proteins, primarily albumin, and is widely distributed into body tissues; lung tissue concentrations are approximately 2 to 5 times higher than plasma concentrations. Levofloxacin undergoes limited metabolism and approximately 87% of a dose is excreted unchanged in urine. Less than 4% of the dose is recovered in the feces. The only metabolites identified in humans are the desmethyl and N-oxide metabolites; these inactive metabolites account for less than 5% of a dose. Renal clearance of levofloxacin is greater than glomerular filtration, suggesting active tubular secretion. The mean elimination half-life in adults is 6 to 8 hours.
     
    Affected cytochrome P450 isoenzymes and drug transporters: none

    Oral Route

    After oral administration, levofloxacin is rapidly absorbed and has an absolute bioavailability of about 99%. Peak plasma concentrations are achieved approximately 1 to 2 hours after an oral dose. Levofloxacin pharmacokinetics are linear and predictable after single and multiple oral dosing regimens. Food prolongs the time to peak by approximately 1 hour and decreases the peak concentration by approximately 14% after tablet administration and 25% after oral solution administration.

    Intravenous Route

    The plasma concentration after IV administration is similar and comparable in extent of exposure (AUC) to that observed with tablet administration. Levofloxacin pharmacokinetics are linear and predictable after single and multiple IV dosing regimens.

    Other Route(s)

    Ophthalmic Route
    After ophthalmic administration, a small amount of levofloxacin is systemically absorbed. In a study of 15 healthy adults, the mean maximum plasma concentrations ranged from 0.94 ng/mL on day 1 to 2.15 ng/mL on day 15.