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    Loop Diuretics

    DEA CLASS

    Rx

    DESCRIPTION

    Oral and parenteral loop diuretic; less potent than bumetanide or ethacrynic acid.

    COMMON BRAND NAMES

    Active-Medicated Specimen Kit, Delone, Diuscreen, Lasix, RX Specimen Collection Kit, Specimen Collection Kit, URINX Medicated Specimen Collection

    HOW SUPPLIED

    Active-Medicated Specimen Kit/Delone/Diuscreen/Furosemide/Lasix/RX Specimen Collection Kit/Specimen Collection Kit/URINX Medicated Specimen Collection Oral Tab: 20mg, 40mg, 80mg
    Furosemide Intramuscular Inj Sol: 1mL, 10mg
    Furosemide Intravenous Inj Sol: 1mL, 10mg
    Furosemide Oral Sol: 1mL, 5mL, 10mg, 40mg

    DOSAGE & INDICATIONS

    For the treatment of peripheral edema or edema associated with heart failure or nephrotic syndrome.
    Oral dosage
    Adults

    Initially, 20—80 mg PO as a single dose; may repeat dose in 6—8 hours. Titrate upward in 20—40 mg increments. The usual dosage is 40—120 mg/day. Maximum dosage is 600 mg/day.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    Infants and Children

    Initially, 1—2 mg/kg/dose PO every 6—12 hours. Maximum dose is 6 mg/kg/dose. Alternatively, for the management of nephrotic syndrome, some experts recommend 1—2 mg/kg/day PO given as a single daily dose or divided into 2 daily doses.

    Premature neonates > 32 weeks postconceptional age

    Doses of 1—4 mg/kg PO, given 1—2 times daily, have been used. Initial doses should not exceed 2 mg/kg. Bioavailability is variable.

    Premature neonates <= 32 weeks postconceptional age

    Initial doses should not exceed 2 mg/kg PO. Because of the risk for accumulation, chronic doses should not be administered more frequently than every 24 hours. Bioavailability is variable.

    Intermittent Intravenous or Intramuscular dosage
    Adults

    Initially, 20—40 mg IV or IM, increasing by 20 mg every 2 hours as needed to attain clinical response. Administer IV doses slowly. A maximum infusion rate of 4 mg/minute has been recommended when administering doses greater than 120 mg or for patients with cardiac or renal failure.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    Infants and Children

    1—2 mg/kg IV or IM every 6—12 hours. Maximum dose is 6 mg/kg/dose.

    Premature neonates > 32 weeks postconceptional age

    1—2 mg/kg IV or IM every 12—24 hours. Use the lowest effective dose.

    Premature neonates <= 32 weeks postconceptional age

    Initial doses should not exceed 1 mg/kg IV. Because of the risk for accumulation, doses should not be administered more frequently than every 24 hours.

    Continuous Intravenous infusion dosage†
    Adults

    The ACC/AHA guidelines for chronic heart failure recommend a dose of 40 mg IV bolus, then 10—40 mg/hour continuous IV infusion.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    For the management of pulmonary edema or prevention of adverse hemodynamic effects associated with blood product transfusions†.
    For the adjunctive treatment of acute pulmonary edema.
    Intravenous or Intramuscular dosage
    Adults

    Initially, 40 mg IV injected slowly; then 80 mg IV injected slowly in 2 hours if needed.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    Children

    Initially, 1—2 mg/kg IV or IM, every 6—12 hours. Maximum dosage is 6 mg/kg/dose.

    Premature neonates > 32 weeks postconceptional age

    1—2 mg/kg IV or IM every 12—24 hours. Use the lowest effective dose.

    Premature neonates <= 32 weeks postconceptional age

    Initial doses should not exceed 1 mg/kg. Because of the risk for accumulation, doses should be administered no more frequently than every 24 hours.

    For the prevention of adverse hemodynamic effects and/or pulmonary edema associated with blood product transfusions†.
    Intravenous dosage
    Adults

    40 mg IV given immediately before whole blood transfusions was found to prevent a significant increase in pulmonary capillary wedge pressure (PCWP) in 2 small prospective trials of patients with chronic severe anemia. In both trials, 1 unit of whole blood was administered at a rate of 5 mL/minute in the furosemide groups with no observed increase in PCWP after the transfusion. The control group received 1 unit of whole blood at a rate of 5 mL/minute in the first trial and 2, 5, or 10 mL/minute in the second trial . The authors reported an increase in PCWP in all control groups after the transfusions.

    Premature neonates

    Although use in clinical practice is not uncommon, limited published data are available evaluating furosemide prior to or after the administration of blood products. One prospective, unblinded trial evaluated furosemide 1 mg/kg IV after transfusions of 10 mL/kg of packed red blood cells (PRBC) in 24 cases; 3 of the 21 infants were studied twice. The infants were 6.1 +/- 2.9 weeks of age (32.5 +/- 3.4 weeks mean gestational age at birth) and all had bronchopulmonary dysplasia. The PRBCs were administered at a rate of 5 mL/kg/hour, and furosemide was given in 16 of the 24 cases. The infants that received furosemide demonstrated an improvement in lung compliance, tidal volume, and minute ventilation compared to baseline. There was no observed improvement in these values in the untreated group. The authors noted no difference in the clinical respiratory status between the 2 groups. Some authors caution against the routine use of furosemide following PRBC transfusions due to a lack of efficacy data and the potential for electrolyte imbalance.

    For adjunctive treatment of edema in patients with acute or chronic renal failure (renal impairment).
    Oral dosage
    Adults

    Initially, 80 mg PO once daily, increasing in increments of 80—120 mg/day until desired clinical response. For immediate diuresis, 320—400 mg once daily has been suggested.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    Intravenous dosage
    Adults

    Initially, 100—200 mg IV. Traditionally, it has been recommended that doses can be doubled every 2—24 hours until desired clinical response, however, most clinicians would probably consider 600—800 mg a maximum dose and either administer a different loop-active agent, or add a second agent in combination with furosemide. A maximum infusion rate of 4 mg/minute has been recommended for doses greater than 120 mg or for patients with cardiac or renal failure.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    For the treatment of hypertension.
    Oral dosage
    Adults

    Initially, 40 mg PO twice daily. Adjust dose according to response. Alternatively, 10—20 mg twice daily adjusting the dose according to clinical response. Maximum dose is 600 mg/day.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    Infants† and Children†

    Although not FDA approved for the treatment of hypertension, doses of 1—2 mg/kg/dose PO given every 6—24 hours have been used for a variety of indications.

    Premature neonates > 32 weeks postconceptional age†

    Doses of 1—4 mg/kg PO, given 1—2 times daily, have been used in this population for various indications. Initial doses should not exceed 2 mg/kg. Bioavailability is variable.

    Premature neonates <= 32 weeks postconceptional age†

    Initial doses should not exceed 2 mg/kg PO. Because of the risk for accumulation, chronic doses should not be administered more frequently than every 24 hours. Bioavailability is variable.

    For adjunctive treatment of hypertensive urgency† or hypertensive emergency†.
    Intravenous dosage
    Adults

    Doses of 40—80 mg IV have been used in patients with normal renal function.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    For the acute treatment of hypercalcemia† associated with neoplastic disease in combination with intravenous saline.
    Intravenous or Intramuscular dosage
    Adults

    Initially, 80—100 mg IV or IM; repeat the dose every 1—2 hours as needed based on clinical response. Less severe cases may use smaller doses every 2—4 hours. Initiate saline administration before the first dose of furosemide to avoid volume contraction which may limit the desired calciuric response.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    Children

    Initially, 25—50 mg IV or IM. The dose may be repeated every 4 hours as needed based on clinical response. Initiate saline administration before the first dose of furosemide to avoid volume contraction which may limit the desired calciuric response.

    For the treatment of ascites† in combination with spironolactone or amiloride.
    Oral dosage
    Adults

    Initially, 40 mg PO once daily, in the morning in combination with spironolactone; dose may be increased after 2—3 days if no clinical response.

    Geriatric

    See adult dosage. Geriatric patients may be more sensitive to the effects of the usual adult dose.

    †Indicates off-label use

    MAXIMUM DOSAGE

    Adults

    600 mg/day PO or 6 g/day IV infusion. Up to 4 g/day PO has been given to treat chronic renal failure.

    Elderly

    600 mg/day PO or 6 g/day IV infusion. Up to 4 g/day PO has been given to treat chronic renal failure.

    Adolescents

    6 mg/kg/dose PO.

    Children

    6 mg/kg/dose PO.

    Infants

    6 mg/kg/dose PO.

    Neonates

    Premature neonates: 1 mg/kg/dose IV is recommended by the manufacturer; doses up to 2 mg/kg IV have been reported for the treatment of edema.

    DOSING CONSIDERATIONS

    Hepatic Impairment

    No specific dosage adjustment is needed; see the dosage for the treatment of ascites. Diuretics should be used with caution in patients with hepatic disease since minor alterations of fluid and electrolyte balance may precipitate hepatic coma.

    Renal Impairment

    No specific dosage adjustments are recommended. Higher doses with extended dosage intervals may be effective in patients with end-stage renal disease (ESRD).

    ADMINISTRATION

    NOTE: In patients with acute or chronic renal failure, larger doses of oral or IV furosemide have been used.
     
    NOTE: The risk of ototoxicity increases with larger doses and/or more rapid parenteral administration of furosemide. A maximum infusion rate of 4 mg/min has been recommended for patients receiving IV doses greater than 120 mg or for patients with cardiac or renal failure.
     
    NOTE: The half-life of furosemide in neonates will be prolonged. Increasing the dosage interval is suggested to help prevent toxicity. Elderly patients may be more sensitive to the effects of normal adult doses.
     

    Oral Administration

    Administer furosemide with meals to minimize indigestion or GI irritation.

    Oral Solid Formulations

    If patient has difficulty swallowing, furosemide tablets may be crushed.

    Oral Liquid Formulations

    When administering furosemide to an infant or child using a medicine dropper or oral syringe, slowly squirt the solution into the side of the child's mouth so that he or she will swallow the liquid naturally. Do not squirt onto the back of the throat because this may cause gagging. Rinse the dropper or syringe in warm water after each use.

    Injectable Administration

    The maximum concentration of furosemide for administration is 10 mg/ml.
    Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.

    Intravenous Administration

    Direct IV injection:
    Inject each 20 mg of furosemide slowly IV over 1—2 minutes.
     
    Intravenous infusion:
    Dilute furosemide in NS, lactated Ringer's, or D5W injection solution; adjust pH to greater than 5.5 when necessary.
    Intermittent IV infusion: Infuse at a rate not to exceed 4 mg/minute in adults or 0.5 mg/kg/minute in children.

    Intramuscular Administration

    No dilution necessary.
    Inject furosemide deeply into a large muscle. Aspirate prior to injection to avoid injection into a blood vessel.

    STORAGE

    Generic:
    - Discard product if it contains particulate matter, is cloudy, or discolored
    - Discard unused portion. Do not store for later use.
    - Protect from light
    - Store between 68 to 77 degrees F, excursions permitted 59 to 86 degrees F
    Active-Medicated Specimen Kit:
    - Store at controlled room temperature (between 68 and 77 degrees F)
    Delone :
    - Store at controlled room temperature (between 68 and 77 degrees F)
    Diuscreen:
    - Store at controlled room temperature (between 68 and 77 degrees F)
    Lasix:
    - Protect from light. Do not dispense discolored product
    - Store at controlled room temperature (between 68 and 77 degrees F)
    RX Specimen Collection Kit:
    - Store at controlled room temperature (between 68 and 77 degrees F)
    Specimen Collection Kit:
    - Store at controlled room temperature (between 68 and 77 degrees F)
    URINX Medicated Specimen Collection:
    - Store at controlled room temperature (between 68 and 77 degrees F)

    CONTRAINDICATIONS / PRECAUTIONS

    Sulfonamide hypersensitivity, thiazide diuretic hypersensitivity

    Furosemide is contraindicated in patients with known hypersensitivity to this drug. Because cross-sensitivity with furosemide has rarely been observed, bumetanide can be substituted for furosemide in patients allergic to furosemide. The risk of an allergic reaction after administration of a loop diuretic in a patient with sulfonamide hypersensitivity or thiazide diuretic hypersensitivity appears to be very low. Although furosemide is a sulfonamide derivative, sulfonamide cross-sensitivity has been rarely documented. A case report, published in 1987, documents an anaphylactic reaction to IV furosemide in a patient who was subsequently skin-tested with furosemide, bumetanide, ethacrynic acid, chlorothiazide, and sulfamethoxazole-trimethoprim. A positive reaction was elicited to all except ethacrynic acid. This case documents hypersensitivity to both furosemide and bumetanide in a patient with sulfonamide hypersensitivity. Prior to this, neither the FDA nor the manufacturer of furosemide (Lasix) had received any reports of cross-sensitivity between furosemide and sulfonamide antibiotics. Furosemide does not contain the N4-aromatic amine or the N1-substituent which are present in sulfonamide antibiotics. Non-arylamine sulfonamide derivatives, such as loop diuretics, have been proposed to have a lower risk of allergic reactions in patients with sulfonamide allergy, presumably due to lack of an arylamine group at the N4 position (a proposed structural site of action for sulfonamide allergy). One large retrospective cohort study has reported that in patients with the presence of an allergic reaction after exposure to a sulfonamide antibiotic, 9.9% had an allergic reaction after receiving a non-antibiotic sulfonamide derivative, while in patients who lacked an allergic reaction after sulfonamide antibiotic exposure, 1.6% had an allergic reaction after administration of a non-antibiotic sulfonamide derivative (adjusted odds ratio 2.8; 95% CI, 2.1—3.7). A causal relationship between sulfonamide hypersensitivity and allergic reactions with non-arylamine sulfonamide derivatives has not been definitively established and remains controversial. In general, patients with a documented sulfonamide allergy are considered to be predisposed for development of allergic drug reactions.

    Acid/base imbalance, electrolyte imbalance, hypocalcemia, hypochloremia, hypokalemia, hypomagnesemia, hyponatremia, metabolic alkalosis

    Preexisting electrolyte imbalance such as severe hyponatremia, hypokalemia, hypocalcemia, hypochloremia, or hypomagnesemia should be corrected before initiating furosemide therapy. Loop diuretics may induce metabolic alkalosis associated with hypokalemia and hypochloremia; this acid/base imbalance is effectively treated with potassium chloride replacement.

    Diabetes mellitus, hyperglycemia

    Blood and urine glucose levels should be assessed in patients with diabetes mellitus or hyperglycemia during treatment with furosemide; loop diuretics can impair glucose tolerance.

    Diarrhea, heart failure, ventricular arrhythmias

    Patients with ventricular arrhythmias, heart failure, potassium-losing nephropathy, aldosterone excess, or diarrhea should be monitored closely since furosemide-induced hypokalemia can exacerbate these conditions.

    Acute myocardial infarction

    Excessive diuresis with furosemide should be avoided in patients with acute myocardial infarction due to the risk of precipitating shock.

    Anuria, hypovolemia, renal disease, renal failure, renal impairment

    Furosemide is contraindicated in patients with anuria. It should be used cautiously in any patient with renal disease such as severe renal impairment or renal failure. Drug-induced hypovolemia can precipitate azotemia in these patients. The presence of hypoproteinemia (e.g., nephrotic syndrome) may weaken the effect of furosemide and increase its potential for ototoxicity. The risk of ototoxicity may also be increased when furosemide is administered to patients with severe renal impairment. Furosemide is an effective diuretic for many patients with renal impairment. Renal impairment may reduce clearance and warrant the use of higher doses with extended dosing intervals. Furosemide may be less effective in these patients and delayed excretion of drug may increase the risk of toxicity.

    Hypotension, orthostatic hypotension, sympathectomy, syncope

    Patients with pre-existing hypovolemia or hypotension should have their condition corrected before furosemide is initiated. Orthostatic hypotension may occur during treatment with loop diuretics. Excessive hypotension can result in syncope. The antihypertensive effects of diuretics may be enhanced in patients predisposed for orthostatic hypotension, including the post-sympathectomy patient.

    Systemic lupus erythematosus (SLE)

    Furosemide has been reported to activate or exacerbate systemic lupus erythematosus (SLE), although the association is less certain than with procainamide or other drugs.

    Gout, hyperuricemia

    Since furosemide can reduce the clearance of uric acid, patients with gout or hyperuricemia can have exacerbations of their disease.

    Hearing impairment

    High doses and accumulation of furosemide may cause ototoxicity. Use furosemide with caution in patients with hearing impairment. Do not exceed the recommended rate of infusion when IV doses are administered.

    Pancreatitis

    Furosemide has been reported to cause pancreatitis. It should be used with caution in patients with a history of pancreatitis.

    Preeclampsia, pregnancy

    Furosemide is classified as FDA pregnancy category C. There are no well-controlled studies of furosemide in pregnant women. After the first trimester, it has been used for edema and hypertension. However, it is important to note that diuretics are generally not recommended for the treatment of pregnancy-induced hypertension (preeclampsia, eclampsia) since they do not alter the course of toxemia and may exacerbate maternal hypovolemia associated with this condition. If furosemide is administered to a pregnant woman, monitoring of fetal growth is required because of the risk for higher birth weights.

    Breast-feeding

    According to the manufacturer, because furosemide appears in breast milk, caution should be exercised when furosemide is administered to a breast-feeding mother. In addition, diuretics such as furosemide may suppress lactation as a result of intense diuresis. Of note, the use of bendroflumethiazide, chlorthalidone, chlorothiazide, and hydrochlorothiazide is considered to be usually compatible with breast-feeding by the American Academy of Pediatrics, due to lack of noted adverse effects on the nursing infant. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally ingested drug, healthcare providers are encouraged to report the adverse effect to the FDA.

    Children, infants, neonates, premature neonates

    Nephrocalcinosis (calcium nephrolithiasis) has occurred in some premature neonates treated with furosemide for edema. Nephrocalcinosis (calcium nephrolithiasis) has also been reported in infants and children under 4 years with no history of prematurity who are receiving chronic furosemide therapy. The concurrent use of chlorothiazide has been reported to decrease hypercalciuria and dissolve some calculi. Pediatric patients receiving furosemide therapy should have their renal function monitored and renal ultrasonography should be considered. In addition, premature neonates who receive furosemide in the first few weeks of life may have an increased risk of persistent patent ductus arteriosus.

    Ascites, hepatic disease, hepatic encephalopathy

    The manufacturer recommends initiating furosemide therapy in the hospital in patients with hepatic disease (i.e., hepatic cirrhosis) and ascites. Furosemide therapy should not be instituted in hepatic encephalopathy (hepatic coma) or in patients with electrolyte depletion until the condition is improved. Rapid fluctuations in fluid and serum electrolyte concentrations can precipitate hepatic coma in patients with cirrhosis. The presence of cirrhosis may also increase the potential for the development of hypokalemia in patients receiving furosemide therapy. Hypokalemia and metabolic alkalosis may be prevented with potassium supplementation and, if necessary, an aldosterone antagonist.

    Prostatic hypertrophy, urethral stricture, urinary retention

    The administration of furosemide to patients with severe symptoms of urinary retention (due to bladder emptying disorders, prostatic hypertrophy, urethral stricture) can precipitate acute urinary retention. This is related to increased production and retention of urine. Monitor these patients carefully, especially during the initiation of furosemide therapy.

    Thyroid disease

    Use high doses (more than 80 mg) of furosemide cautiously in patients with thyroid disease. At high doses, furosemide may inhibit the binding of thyroid hormones to carrier proteins, resulting in a transient increase in free thyroid hormones followed by an overall decrease in total thyroid hormone concentrations.

    Geriatric

    Greater sensitivity to the hypotensive and diuretic effects of furosemide is possible in geriatric patients. Reported clinical experience has not identified differences in responses between older adult and younger adult patients. In general, dose selection for elderly patients should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy. Furosemide is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection and it may be useful to monitor renal function. According to the Beers Criteria, diuretics are considered potentially inappropriate medications (PIMs) in geriatric patients and should be used with caution due to the potential for causing or exacerbating SIADH or hyponatremia; sodium levels should be closely monitored when starting or changing dosages of diuretics in older adults. The federal Omnibus Budget Reconciliation Act (OBRA) regulates medication use in residents of long-term care facilities. According to the OBRA guidelines, antihypertensive regimens should be individualized to achieve the desired outcome while minimizing adverse effects. Antihypertensives may cause dizziness, postural hypotension, fatigue, and there is an increased risk for falls. Diuretics may cause fluid and electrolyte imbalances and may precipitate or exacerbate urinary incontinence. Furosemide has anticholinergic properties which may be problematic in the elderly. There are many drug interactions that can potentiate the effects of antihypertensives.

    ADVERSE REACTIONS

    Severe

    hepatic encephalopathy / Delayed / Incidence not known
    pancreatitis / Delayed / Incidence not known
    interstitial nephritis / Delayed / Incidence not known
    azotemia / Delayed / Incidence not known
    oliguria / Early / Incidence not known
    thromboembolism / Delayed / Incidence not known
    thrombosis / Delayed / Incidence not known
    hearing loss / Delayed / Incidence not known
    hemolytic anemia / Delayed / Incidence not known
    aplastic anemia / Delayed / Incidence not known
    agranulocytosis / Delayed / Incidence not known
    toxic epidermal necrolysis / Delayed / Incidence not known
    acute generalized exanthematous pustulosis (AGEP) / Delayed / Incidence not known
    Stevens-Johnson syndrome / Delayed / Incidence not known
    Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) / Delayed / Incidence not known
    exfoliative dermatitis / Delayed / Incidence not known
    erythema multiforme / Delayed / Incidence not known
    anaphylactoid reactions / Rapid / Incidence not known
    anaphylactic shock / Rapid / Incidence not known
    vasculitis / Delayed / Incidence not known

    Moderate

    hypokalemia / Delayed / 38.0-38.0
    hypomagnesemia / Delayed / 12.4-12.4
    elevated hepatic enzymes / Delayed / Incidence not known
    constipation / Delayed / Incidence not known
    jaundice / Delayed / Incidence not known
    cholestasis / Delayed / Incidence not known
    xanthopsia / Delayed / Incidence not known
    blurred vision / Early / Incidence not known
    hyponatremia / Delayed / Incidence not known
    metabolic alkalosis / Delayed / Incidence not known
    hypochloremia / Delayed / Incidence not known
    hypocalcemia / Delayed / Incidence not known
    hypovolemia / Early / Incidence not known
    orthostatic hypotension / Delayed / Incidence not known
    phlebitis / Rapid / Incidence not known
    gout / Delayed / Incidence not known
    hyperuricemia / Delayed / Incidence not known
    hyperglycemia / Delayed / Incidence not known
    diabetes mellitus / Delayed / Incidence not known
    glycosuria / Early / Incidence not known
    hypertriglyceridemia / Delayed / Incidence not known
    hypercholesterolemia / Delayed / Incidence not known
    anemia / Delayed / Incidence not known
    eosinophilia / Delayed / Incidence not known
    leukopenia / Delayed / Incidence not known
    thrombocytopenia / Delayed / Incidence not known
    bullous rash / Early / Incidence not known
    bladder spasm / Early / Incidence not known

    Mild

    vomiting / Early / Incidence not known
    abdominal pain / Early / Incidence not known
    nausea / Early / Incidence not known
    diarrhea / Early / Incidence not known
    anorexia / Delayed / Incidence not known
    dizziness / Early / Incidence not known
    paresthesias / Delayed / Incidence not known
    restlessness / Early / Incidence not known
    vertigo / Early / Incidence not known
    headache / Early / Incidence not known
    polyuria / Early / Incidence not known
    syncope / Early / Incidence not known
    tinnitus / Delayed / Incidence not known
    weakness / Early / Incidence not known
    fever / Early / Incidence not known
    purpura / Delayed / Incidence not known
    pruritus / Rapid / Incidence not known
    rash (unspecified) / Early / Incidence not known
    photosensitivity / Delayed / Incidence not known
    urticaria / Rapid / Incidence not known
    muscle cramps / Delayed / Incidence not known
    injection site reaction / Rapid / Incidence not known

    DRUG INTERACTIONS

    Acarbose: (Minor) Loop diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Acetaminophen; Chlorpheniramine; Phenylephrine; Phenyltoloxamine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Acetaminophen; Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Acetaminophen; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Acetaminophen; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Acetaminophen; Dichloralphenazone; Isometheptene: (Major) Isometheptene has sympathomimetic properties. Patients taking antihypertensive agents may need to have their therapy modified. Careful blood pressure monitoring is recommended.
    Acetaminophen; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Acetaminophen; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Acetazolamide: (Moderate) Carbonic anhydrase inhibitors promote electrolyte excretion including hydrogen ions, sodium, and potassium. They can enhance the sodium depleting effects of other diuretics when used concurrently. Pre-existing hypokalemia and hyperuricemia can also be potentiated by carbonic anhydrase inhibitors. Monitor serum potassium to determine the need for potassium supplementation and alteration in drug therapy.
    Acetohexamide: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Acrivastine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Albiglutide: (Minor) Loop diuretics, such as bumetanide, furosemide, and torsemide, may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, including incretin mimetics. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Alemtuzumab: (Moderate) Alemtuzumab may cause hypotension. Careful monitoring of blood pressure and hypotensive symptoms is recommended especially in patients with ischemic heart disease and in patients on antihypertensive agents.
    Alendronate: (Moderate) When the intravenous formulation of alendronate is used for the treatment of hypercalcemia of malignancy, combination therapy with loop diuretics should be used with caution in order to avoid hypocalcemia. In patients with hypercalcemia of malignancy, the initial treatment typically includes the use of loop diuretics, in combination with saline hydration, however, diuretic therapy should not be employed prior to correction of hypovolemia and dehydration.
    Alendronate; Cholecalciferol: (Moderate) When the intravenous formulation of alendronate is used for the treatment of hypercalcemia of malignancy, combination therapy with loop diuretics should be used with caution in order to avoid hypocalcemia. In patients with hypercalcemia of malignancy, the initial treatment typically includes the use of loop diuretics, in combination with saline hydration, however, diuretic therapy should not be employed prior to correction of hypovolemia and dehydration.
    Aliskiren: (Moderate) Aliskiren can enhance the effects of loop-diuretics on blood pressure if given concomitantly. This additive effect may be desirable, but dosages must be adjusted accordingly. Patients with hyponatremia or hypovolemia may also develop reversible renal insufficiency. When aliskiren is administered in combination with furosemide, the AUC and Cmax of furosemide are reduced by approximately 30% and 50%, respectively; the pharmacokinetics of aliskiren are not affected. Patients should be monitored for loss of effect of furosemide when aliskiren is initiated. Blood pressure and electrolytes should be routinely monitored.
    Aliskiren; Amlodipine: (Moderate) Aliskiren can enhance the effects of loop-diuretics on blood pressure if given concomitantly. This additive effect may be desirable, but dosages must be adjusted accordingly. Patients with hyponatremia or hypovolemia may also develop reversible renal insufficiency. When aliskiren is administered in combination with furosemide, the AUC and Cmax of furosemide are reduced by approximately 30% and 50%, respectively; the pharmacokinetics of aliskiren are not affected. Patients should be monitored for loss of effect of furosemide when aliskiren is initiated. Blood pressure and electrolytes should be routinely monitored.
    Aliskiren; Amlodipine; Hydrochlorothiazide, HCTZ: (Moderate) Aliskiren can enhance the effects of loop-diuretics on blood pressure if given concomitantly. This additive effect may be desirable, but dosages must be adjusted accordingly. Patients with hyponatremia or hypovolemia may also develop reversible renal insufficiency. When aliskiren is administered in combination with furosemide, the AUC and Cmax of furosemide are reduced by approximately 30% and 50%, respectively; the pharmacokinetics of aliskiren are not affected. Patients should be monitored for loss of effect of furosemide when aliskiren is initiated. Blood pressure and electrolytes should be routinely monitored. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Aliskiren; Hydrochlorothiazide, HCTZ: (Moderate) Aliskiren can enhance the effects of loop-diuretics on blood pressure if given concomitantly. This additive effect may be desirable, but dosages must be adjusted accordingly. Patients with hyponatremia or hypovolemia may also develop reversible renal insufficiency. When aliskiren is administered in combination with furosemide, the AUC and Cmax of furosemide are reduced by approximately 30% and 50%, respectively; the pharmacokinetics of aliskiren are not affected. Patients should be monitored for loss of effect of furosemide when aliskiren is initiated. Blood pressure and electrolytes should be routinely monitored. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Aliskiren; Valsartan: (Moderate) Aliskiren can enhance the effects of loop-diuretics on blood pressure if given concomitantly. This additive effect may be desirable, but dosages must be adjusted accordingly. Patients with hyponatremia or hypovolemia may also develop reversible renal insufficiency. When aliskiren is administered in combination with furosemide, the AUC and Cmax of furosemide are reduced by approximately 30% and 50%, respectively; the pharmacokinetics of aliskiren are not affected. Patients should be monitored for loss of effect of furosemide when aliskiren is initiated. Blood pressure and electrolytes should be routinely monitored. (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Alogliptin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents, including alogliptin. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if this drug is initiated.
    Alogliptin; Metformin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents, including alogliptin. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if this drug is initiated.
    Alogliptin; Pioglitazone: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents, including alogliptin. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if this drug is initiated. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Alpha-glucosidase Inhibitors: (Minor) Loop diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Alprostadil: (Minor) The concomitant use of systemic alprostadil injection and antihypertensive agents, such as loop diuretics, may cause additive hypotension. Caution is advised with this combination. Systemic drug interactions with the urethral suppository (MUSE) or alprostadil intracavernous injection are unlikely in most patients because low or undetectable amounts of the drug are found in the peripheral venous circulation following administration. In those men with significant corpora cavernosa venous leakage, hypotension might be more likely. Use caution with in-clinic dosing for erectile dysfunction (ED) and monitor for the effects on blood pressure. In addition, the presence of medications in the circulation that attenuate erectile function may influence the response to alprostadil. However, in clinical trials with alprostadil intracavernous injection, anti-hypertensive agents had no apparent effect on the safety and efficacy of alprostadil.
    Aluminum Hydroxide; Magnesium Hydroxide: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Aluminum Hydroxide; Magnesium Hydroxide; Simethicone: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Amikacin: (Moderate) The risk of ototoxicity or nephrotoxicity secondary to aminoglycosides may be increased by the addition of concomitant therapies with similar side effects, including loop diuretics. If loop diuretics and aminoglycosides are used together, it would be prudent to monitor renal function parameters, serum electrolytes, and serum aminoglycoside concentrations during therapy. Audiologic monitoring may be advisable during high dose therapy or therapy of long duration, when hearing loss is suspected, or in selected risk groups (e.g., neonates).
    Amiloride; Hydrochlorothiazide, HCTZ: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Aminoglycosides: (Moderate) The risk of ototoxicity or nephrotoxicity secondary to aminoglycosides may be increased by the addition of concomitant therapies with similar side effects, including loop diuretics. If loop diuretics and aminoglycosides are used together, it would be prudent to monitor renal function parameters, serum electrolytes, and serum aminoglycoside concentrations during therapy. Audiologic monitoring may be advisable during high dose therapy or therapy of long duration, when hearing loss is suspected, or in selected risk groups (e.g., neonates).
    Amiodarone: (Major) Monitor serum electrolytes if coadministration of furosemide and amiodarone is necessary. Furosemide therapy may cause electrolyte abnormalities (i.e., hypokalemia, hypomagnesemia) which can exaggerate the degree of QTc prolongation and increase the potential for torsade de pointes.
    Amlodipine; Benazepril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Amlodipine; Hydrochlorothiazide, HCTZ; Olmesartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Amlodipine; Hydrochlorothiazide, HCTZ; Valsartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Amlodipine; Olmesartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Amlodipine; Telmisartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Amlodipine; Valsartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Amobarbital: (Moderate) Concurrent use of amobarbital with antihypertensive agents may lead to hypotension. Monitor for decreases in blood pressure during times of coadministration.
    Amoxicillin: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Amoxicillin; Clarithromycin; Lansoprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement. (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Amoxicillin; Clarithromycin; Omeprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement. (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Amoxicillin; Clavulanic Acid: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Amphetamine: (Major) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, such as loop diuretics. Close monitoring of blood pressure or the selection of alternative therapeutic agents may be needed.
    Amphetamine; Dextroamphetamine Salts: (Major) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, such as loop diuretics. Close monitoring of blood pressure or the selection of alternative therapeutic agents may be needed.
    Amphetamine; Dextroamphetamine: (Major) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, such as loop diuretics. Close monitoring of blood pressure or the selection of alternative therapeutic agents may be needed.
    Amphotericin B cholesteryl sulfate complex (ABCD): (Moderate) Amphotericin B-induced hypokalemia can result in interactions with other drugs. Concurrent use of amphotericin B with loop diuretics can cause additive hypokalemia or hypomagnesemia due to renal potassium and magnesium wasting. It is prudent to monitor renal function parameters and serum electrolyte concentrations during co-therapy with loop diuretics and drugs which induce hypokalemia.
    Amphotericin B lipid complex (ABLC): (Moderate) Amphotericin B-induced hypokalemia can result in interactions with other drugs. Concurrent use of amphotericin B with loop diuretics can cause additive hypokalemia or hypomagnesemia due to renal potassium and magnesium wasting. It is prudent to monitor renal function parameters and serum electrolyte concentrations during co-therapy with loop diuretics and drugs which induce hypokalemia.
    Amphotericin B liposomal (LAmB): (Moderate) Amphotericin B-induced hypokalemia can result in interactions with other drugs. Concurrent use of amphotericin B with loop diuretics can cause additive hypokalemia or hypomagnesemia due to renal potassium and magnesium wasting. It is prudent to monitor renal function parameters and serum electrolyte concentrations during co-therapy with loop diuretics and drugs which induce hypokalemia.
    Amphotericin B: (Moderate) Amphotericin B-induced hypokalemia can result in interactions with other drugs. Concurrent use of amphotericin B with loop diuretics can cause additive hypokalemia or hypomagnesemia due to renal potassium and magnesium wasting. It is prudent to monitor renal function parameters and serum electrolyte concentrations during co-therapy with loop diuretics and drugs which induce hypokalemia.
    Ampicillin: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Ampicillin; Sulbactam: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Amyl Nitrite: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
    Angiotensin II receptor antagonists: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Angiotensin-converting enzyme inhibitors: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Apomorphine: (Moderate) Patients receiving apomorphine may experience orthostatic hypotension, hypotension, and/or syncope. Extreme caution should be exercised if apomorphine is used concurrently with antihypertensive agents, or vasodilators such as nitrates.
    Apraclonidine: (Minor) Alpha blockers as a class may reduce heart rate and blood pressure. While no specific drug interactions have been identified with systemic agents and apraclonidine during clinical trials, it is theoretically possible that additive blood pressure reductions could occur when apraclonidine is combined with the use of antihypertensive agents. Patients using cardiovascular drugs concomitantly with apraclonidine should have their pulse and blood pressure monitored periodically.
    Aripiprazole: (Minor) Aripiprazole may enhance the hypotensive effects of antihypertensive agents.
    Arsenic Trioxide: (Major) Because electrolyte abnormalities increase the risk of QT interval prolongation and serious arrhythmias, avoid the concomitant use of arsenic trioxide with drugs that may cause electrolyte abnormalities, particularly hypokalemia and hypomagnesemia. Examples of drugs that may cause electrolyte abnormalities includes loop diuretics. If concomitant drug use is unavoidable, frequently monitor serum electrolytes (and replace as necessary) and electrocardiograms.
    Asenapine: (Moderate) Secondary to alpha-blockade, asenapine can produce vasodilation that may result in additive effects during concurrent use of antihypertensive agents. The potential reduction in blood pressure can precipitate orthostatic hypotension and associated dizziness, tachycardia, and syncope. If concurrent use of asenapine and antihypertensive agents is necessary, patients should be counseled on measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning and rising slowly from a seated position. Close monitoring of blood pressure is recommended until the full effects of the combination therapy are known.
    Aspirin, ASA; Omeprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Atenolol; Chlorthalidone: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Atracurium: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Azelaic Acid; Copper; Folic Acid; Nicotinamide; Pyridoxine; Zinc: (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents. (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents. This effect is of particular concern in the setting of acute myocardial infarction, unstable angina, or other acute hemodynamic compromise.
    Azelastine; Fluticasone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Azilsartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Azilsartan; Chlorthalidone: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Bacitracin: (Minor) Additive nephrotoxicity may occur with concurrent use of systemic bacitracin and other nephrotoxic agents. When possible, avoid concomitant administration of systemic bacitracin and other nephrotoxic drugs such as loop diuretics. Topical administration of any preparation containing bacitracin, especially when applied to large surface areas, also should not be given with other drugs that have a nephrotoxic potential. (Minor) Additive nephrotoxicity may occur with concurrent use of these medicines. When possible, avoid concomitant administration of systemic bacitracin and loop diuretics. Use of topically administrated preparations containing bacitracin, especially when applied to large surface areas, may have additive nephrotoxic potential with loop diuretics.
    Bacitracin; Hydrocortisone; Neomycin; Polymyxin B: (Minor) Additive nephrotoxicity may occur with concurrent use of systemic bacitracin and other nephrotoxic agents. When possible, avoid concomitant administration of systemic bacitracin and other nephrotoxic drugs such as loop diuretics. Topical administration of any preparation containing bacitracin, especially when applied to large surface areas, also should not be given with other drugs that have a nephrotoxic potential.
    Bacitracin; Neomycin; Polymyxin B: (Minor) Additive nephrotoxicity may occur with concurrent use of systemic bacitracin and other nephrotoxic agents. When possible, avoid concomitant administration of systemic bacitracin and other nephrotoxic drugs such as loop diuretics. Topical administration of any preparation containing bacitracin, especially when applied to large surface areas, also should not be given with other drugs that have a nephrotoxic potential.
    Bacitracin; Polymyxin B: (Minor) Additive nephrotoxicity may occur with concurrent use of systemic bacitracin and other nephrotoxic agents. When possible, avoid concomitant administration of systemic bacitracin and other nephrotoxic drugs such as loop diuretics. Topical administration of any preparation containing bacitracin, especially when applied to large surface areas, also should not be given with other drugs that have a nephrotoxic potential.
    Baclofen: (Moderate) Baclofen has been associated with hypotension. Concurrent use with baclofen and antihypertensive agents may result in additive hypotension. Dosage adjustments of the antihypertensive medication may be required.
    Beclomethasone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Benazepril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Benazepril; Hydrochlorothiazide, HCTZ: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Bendroflumethiazide; Nadolol: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Benzphetamine: (Major) Benzphetamine can increase both systolic and diastolic blood pressure and may counteract the activity of loop diuretics. This represents a pharmacodynamic, and not a pharmacokinetic, interaction. Close monitoring of blood pressure, especially in patients who are taking antihypertensive agents, may be needed.
    Beta-agonists: (Moderate) Loop diuretics may potentiate hypokalemia and ECG changes seen with beta agonists. Hypokalemia due to beta agonists appears to be dose related and is more likely with high dose therapy. Caution is advised when loop diuretics are coadministered with high doses of beta agonists; potassium levels may need to be monitored.
    Betamethasone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Bisacodyl: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Bisoprolol; Hydrochlorothiazide, HCTZ: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Bosentan: (Moderate) Although no specific interactions have been documented, bosentan has vasodilatory effects and may contribute additive hypotensive effects when given with diuretics.
    Brexpiprazole: (Moderate) Due to brexpiprazole's antagonism at alpha 1-adrenergic receptors, the drug may enhance the hypotensive effects of alpha-blockers and other antihypertensive agents.
    Bromocriptine: (Minor) Bromocriptine has only minimal affinity for adrenergic receptors; however, hypotension can occur during bromocriptine administration. Orthostatic hypotension occurs in 6% of acromegaly patients receiving the drug. Hypotension occurred frequently (approximately 30%) in postpartum studies, which in rare cases approached a decline in supine pressure of almost 60 mmHg. It is unknown if bromocriptine is the exact cause of this effect. However, the drug should be used cautiously with other medications known to lower blood pressure such as antihypertensive agents. Monitoring of blood pressure should be considered, especially during the initial weeks of concomitant therapy.
    Brompheniramine; Carbetapentane; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Brompheniramine; Hydrocodone; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Brompheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Budesonide: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Budesonide; Formoterol: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Cabergoline: (Minor) Cabergoline has minimal affinity for adrenergic receptors; however, it has been associated with hypotension in some instances. Cabergoline should be used cautiously in those receiving antihypertensive agents.
    Cabozantinib: (Major) Monitor for an increase in cabozantinib-related adverse events if concomitant use with furosemide is necessary, as plasma concentrations of cabozantinib may be increased. Furosemide is a Multidrug Resistance Protein 2 (MRP2) inhibitor and cabozantinib is a substrate of MRP2; the clinical relevance of this finding is unknown.
    Calcium Carbonate; Magnesium Hydroxide: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Calcium Phosphate, Supersaturated: (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as diuretics, may increase the risk of acute phosphate nephropathy in patients receiving sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous. In addition, loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Canagliflozin: (Moderate) When canagliflozin is initiated in patients already receiving diuretics, symptomatic hypotension can occur. Patients with impaired renal function (eGFR < 60 ml/min/1.73 m2), low systolic blood pressure, or who are elderly may also be at a greater risk. Before initiating canagliflozin in patients with one or more of these characteristics, volume status should be assessed and corrected. Monitor for signs and symptoms after initiating therapy. In addition, loop diuretics can also decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. Patients receiving canagliflozin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
    Canagliflozin; Metformin: (Moderate) When canagliflozin is initiated in patients already receiving diuretics, symptomatic hypotension can occur. Patients with impaired renal function (eGFR < 60 ml/min/1.73 m2), low systolic blood pressure, or who are elderly may also be at a greater risk. Before initiating canagliflozin in patients with one or more of these characteristics, volume status should be assessed and corrected. Monitor for signs and symptoms after initiating therapy. In addition, loop diuretics can also decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. Patients receiving canagliflozin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia.
    Candesartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Candesartan; Hydrochlorothiazide, HCTZ: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Capreomycin: (Moderate) The risk of ototoxicity or nephrotoxicity secondary to capreomycin may be increased by the addition of concomitant therapies with similar side effects, including loop diuretics. Ototoxicity from furosemide or other loop diuretics, while uncommon, can be a transient or permanent side effect of significance. Ototoxicity is best documented with the loop diuretics ethacrynic acid and furosemide, but may also occur with either bumetanide or torsemide. The exact mechanism by which furosemide or other loop diuretics produce ototoxicity is unknown. Usually, reports indicate that furosemide ototoxicity is associated with rapid injection, severe renal impairment, higher than recommended dosages or infusion rates, or concomitant therapy with aminoglycoside antibiotics, ethacrynic acid, or other ototoxic drugs. If loop diuretics and capreomycin are used together, it would be prudent to monitor renal function parameters, serum electrolytes, and serum aminoglycoside concentrations during therapy. Audiologic monitoring may be advisable during high dose therapy or therapy of long duration, when hearing loss is suspected, or in selected risk groups (e.g., neonates).
    Captopril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Captopril; Hydrochlorothiazide, HCTZ: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Carbenicillin: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Carbetapentane; Chlorpheniramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Carbetapentane; Diphenhydramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Carbetapentane; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Carbetapentane; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Carbetapentane; Phenylephrine; Pyrilamine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Carbetapentane; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Carbidopa; Levodopa: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects.
    Carbidopa; Levodopa; Entacapone: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects.
    Carbinoxamine; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Carbinoxamine; Hydrocodone; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Carbinoxamine; Hydrocodone; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Carbinoxamine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Carbinoxamine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Cardiac glycosides: (Moderate) Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics, increasing the risk of proarrhythmic effects of cardiac glycosides. Potassium levels should be monitored and normalized prior to and during concurrent diuretic administration and these agents.
    Cariprazine: (Moderate) Orthostatic vital signs should be monitored in patients who are at risk for hypotension, such as those receiving cariprazine in combination with antihypertensive agents. Atypical antipsychotics may cause orthostatic hypotension and syncope, most commonly during treatment initiation and dosage increases. Patients should be informed about measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning, or rising slowly from a seated position. Consider a cariprazine dose reduction if hypotension occurs.
    Casanthranol; Docusate Sodium: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Castor Oil: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Cefaclor: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefadroxil: (Severe) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefazolin: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefdinir: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefditoren: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefepime: (Minor) Cefepime's product label states that cephalosporins may potentiate the adverse renal effects of nephrotoxic agents, such as aminoglycosides and loop diuretics. Carefully monitor renal function, especially during prolonged therapy or use of high aminoglycoside doses. The majority of reported cases involve the combination of aminoglycosides and cephalothin or cephaloridine, which are associated with dose-related nephrotoxicity as singular agents. Limited but conflicting data with other cephalosporins have been noted.
    Cefixime: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefoperazone: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefotaxime: (Minor) Cefotaxime's product label states that cephalosporins may potentiate the adverse renal effects of nephrotoxic agents, such as aminoglycosides and loop diuretics. Carefully monitor renal function, especially during prolonged therapy or use of high aminoglycoside doses. The majority of reported cases involve the combination of aminoglycosides and cephalothin or cephaloridine, which are associated with dose-related nephrotoxicity as singular agents. Limited but conflicting data with other cephalosporins have been noted.
    Cefotetan: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefoxitin: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefpodoxime: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefprozil: (Minor) Cefprozil's product label states that cephalosporins may potentiate the adverse renal effects of nephrotoxic agents, such as aminoglycosides and loop diuretics. Carefully monitor renal function, especially during prolonged therapy or use of high aminoglycoside doses. The majority of reported cases involve the combination of aminoglycosides and cephalothin or cephaloridine, which are associated with dose-related nephrotoxicity as singular agents. Limited but conflicting data with other cephalosporins have been noted.
    Ceftaroline: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Ceftazidime: (Minor) Ceftazidime's product label states that cephalosporins may potentiate the adverse renal effects of nephrotoxic agents, such as aminoglycosides and loop diuretics. Carefully monitor renal function, especially during prolonged therapy or use of high aminoglycoside doses. The majority of reported cases involve the combination of aminoglycosides and cephalothin or cephaloridine, which are associated with dose-related nephrotoxicity as singular agents. Limited but conflicting data with other cephalosporins have been noted.
    Ceftazidime; Avibactam: (Minor) Ceftazidime's product label states that cephalosporins may potentiate the adverse renal effects of nephrotoxic agents, such as aminoglycosides and loop diuretics. Carefully monitor renal function, especially during prolonged therapy or use of high aminoglycoside doses. The majority of reported cases involve the combination of aminoglycosides and cephalothin or cephaloridine, which are associated with dose-related nephrotoxicity as singular agents. Limited but conflicting data with other cephalosporins have been noted.
    Ceftibuten: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Ceftizoxime: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Ceftriaxone: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cefuroxime: (Minor) Cefuroxime's product label states that cephalosporins may potentiate the adverse renal effects of nephrotoxic agents, such as aminoglycosides and loop diuretics. Carefully monitor renal function, especially during prolonged therapy or use of high aminoglycoside doses. The majority of reported cases involve the combination of aminoglycosides and cephalothin or cephaloridine, which are associated with dose-related nephrotoxicity as singular agents. Limited but conflicting data with other cephalosporins have been noted.
    Celecoxib: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Cephalexin: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cephradine: (Moderate) Nephrotoxicity associated with cephalosporins may be potentiated by concomitant furosemide therapy. Clinicans should be aware that this may occur even in patients with minor or transient renal impairment.
    Cetirizine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Chlophedianol; Dexchlorpheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Chlophedianol; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Chloral Hydrate: (Major) According to the manufacturer, coadministration of furosemide with chloral hydrate is not recommended. Intravenous administration of furosemide within 24 hours of taking chloral hydrate has resulted in flushing, sweating, restlessness, nausea, increased blood pressure, and tachycardia in isolated cases.
    Chloroprocaine: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
    Chlorothiazide: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Chlorpheniramine; Dihydrocodeine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Chlorpheniramine; Dihydrocodeine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Chlorpheniramine; Guaifenesin; Hydrocodone; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Chlorpheniramine; Hydrocodone; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Chlorpheniramine; Hydrocodone; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Chlorpheniramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Chlorpheniramine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Chlorpropamide: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Chlorthalidone: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Chlorthalidone; Clonidine: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Cholestyramine: (Moderate) In a study of 6 healthy volunteers, concurrent administration of cholestyramine with oral furosemide reduced the bioavailability of furosemide by 95% and reduced the diuretic response by 77%. Concomitant administration with colestipol reduced furosemide bioavailability by 80% and the diuretic response by 58%. The manufacturer of colestipol recommends administering other drugs at least 1 hour before or at least 4-6 hours after the administration of colestipol and that the interval between the administration of colestipol and other drugs should be as long as possible.
    Ciclesonide: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Cidofovir: (Severe) The administration of cidofovir with another potentially nephrotoxic agent, such as diuretics, is contraindicated. Diuretics should be discontinued at least 7 days prior to beginning cidofovir.
    Cisapride: (Major) Cisapride should be used with great caution in patients receiving potassium-wasting diuretic therapies, such as loop diuretics. Drugs that are associated with depletion of electrolytes may cause cisapride-induced cardiac arrhythmias.
    Cisatracurium: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Cisplatin: (Moderate) Concurrent use of cisplatin and other agents known to be ototoxic (e.g., loop diuretics) may increase the risk of drug-induced ototoxicity, but confirmatory data are not available. Usually, reports indicate that furosemide ototoxicity is associated with rapid injection, severe renal impairment, higher than recommended furosemide dosages or infusion rates, hypoproteinemia, or concomitant therapy with other ototoxic drugs. Additive effects of cisplatin and loop diuretics on renal parameters and electrolyte balance should also be considered. Saline hydration and diuretic use are common during cisplatin therapy to manage hydration status. If furosemide and cisplatin are used together, it is prudent to monitor renal function parameters and serum electrolyte concentrations during co-therapy. Audiologic monitoring may be advisable during high dose therapy or therapy of long duration, when hearing loss is suspected, or in selected risk groups.
    Citalopram: (Moderate) Citalopram causes dose-dependent QT interval prolongation. Concurrent use of citalopram and medications known to cause electrolyte imbalance may increase the risk of developing QT prolongation. Therefore, caution is advisable during concurrent use of citalopram and diuretics. In addition, patients receiving a diuretic during treatment with citalopram may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH has been reported during therapy with SSRIs. Cases involving serum sodium levels lower than 110 mmol/l have occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of citalopram should be considered in patients who develop symptomatic hyponatremia.
    Clozapine: (Major) Caution is advisable during concurrent use of clozapine and loop diuretics. Treatment with clozapine has been associated with QT prolongation, torsade de pointes (TdP), cardiac arrest, and sudden death. Concurrent use of clozapine and medications known to cause electrolyte imbalance may increase the risk of QT prolongation.
    Cod Liver Oil: (Moderate) Fish oil supplements may cause mild, dose-dependent reductions in systolic or diastolic blood pressure in untreated hypertensive patients. Relatively high doses of fish oil are required to produce any blood pressure lowering effect. Additive reductions in blood pressure may be seen when fish oils are used in a patient already taking antihypertensive agents. (Moderate) High doses of fish oil supplements may produce a blood pressure lowering effect. It is possible that additive reductions in blood pressure may be seen when fish oils are used in a patient already taking antihypertensive agents.
    Codeine; Phenylephrine; Promethazine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Co-Enzyme Q10, Ubiquinone: (Moderate) Co-enzyme Q10, ubiquinone (CoQ10) may lower blood pressure. CoQ10 use in combination with antihypertensive agents may lead to additional reductions in blood pressure in some individuals. Patients who choose to take CoQ10 concurrently with antihypertensive medications should receive periodic blood pressure monitoring. Patients should be advised to inform their prescriber of their use of CoQ10.
    Colestipol: (Moderate) In a study of 6 healthy volunteers, concurrent administration of cholestyramine with oral furosemide reduced the bioavailability of furosemide by 95% and reduced the diuretic response by 77%. Concomitant administration with colestipol reduced furosemide bioavailability by 80% and the diuretic response by 58%. The manufacturer of colestipol recommends administering other drugs at least 1 hour before or at least 4-6 hours after the administration of colestipol and that the interval between the administration of colestipol and other drugs should be as long as possible.
    Conivaptan: (Moderate) There is potential for additive hypotensive effects when conivaptan is coadministered with antihypertensive agents.
    Corticosteroids: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Corticotropin, ACTH: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Cortisone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Cosyntropin: (Moderate) Use cosyntropin cautiously in patients receiving diuretics. Cosyntropin may accentuate the electrolyte loss associated with diuretic therapy.
    Cyclosporine: (Moderate) Coadministration of furosemide and cyclosporine increases the risk of gouty arhtritis. This is a result of furosemide-induced hyperuricemia and the impairment of renal urate excretion by cyclosporine.
    Dapagliflozin: (Moderate) Loop diuretics can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. Patients receiving dapagliflozin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
    Dapagliflozin; Metformin: (Moderate) Loop diuretics can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. Patients receiving dapagliflozin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia.
    Dapagliflozin; Saxagliptin: (Moderate) Loop diuretics can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. Patients receiving dapagliflozin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Darifenacin: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms.
    Dasabuvir; Ombitasvir; Paritaprevir; Ritonavir: (Moderate) The manufacturer of dasabuvir; ombitasvir; paritaprevir; ritonavir and ombitasvir; paritaprevir; ritonavir recommends caution and clinical monitoring if administered concurrently with furosemide. Use of these drugs in combination has resulted in elevated furosemide maximum plasma concentrations (Cmax). Individualize the dose of furosemide based on the patient's clinical response. The dose should be re-adjusted after completion of the hepatitis C treatment regimen. (Moderate) The manufacturer of dasabuvir; ombitasvir; paritaprevir; ritonavir recommends caution and clinical monitoring if administered concurrently with furosemide. Use of these drugs in combination has resulted in elevated furosemide maximum plasma concentrations (Cmax). Individualize the dose of furosemide based on the patient's clinical response. The dose should be re-adjusted after completion of the 4-drug hepatitis C treatment regimen.
    Deflazacort: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Desiccated Thyroid: (Moderate) Use high doses (more than 80 mg) of furosemide and thyroid hormones together with caution. High doses of furosemide may inhibit the binding of thyroid hormones to carrier proteins, resulting in a transient increase in free thyroid hormones followed by an overall decrease in total thyroid hormone concentrations.
    Desloratadine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Desmopressin: (Major) Desmopressin, when used in the treatment of nocturia is contraindicated with loop diuretics because of the risk of severe hyponatremia.
    Desvenlafaxine: (Moderate) Patients receiving a diuretic during treatment with venlafaxine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH may occur during therapy with SNRIs, including venlafaxine. Cases involving serum sodium levels lower than 110 mmol/l have been reported. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of the SNRI should be considered in patients who develop symptomatic hyponatremia.
    Dexamethasone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Dexlansoprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Dexmethylphenidate: (Moderate) Dexmethylphenidate can reduce the hypotensive effect of antihypertensive agents, including loop diuretics. Periodic evaluation of blood pressure is advisable during concurrent use of dexmethylphenidate and antihypertensive agents, particularly during initial coadministration and after dosage increases of dexmethylphenidate.
    Dextroamphetamine: (Major) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, such as loop diuretics. Close monitoring of blood pressure or the selection of alternative therapeutic agents may be needed.
    Dextromethorphan; Diphenhydramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Dextromethorphan; Quinidine: (Moderate) Quinidine can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents due to the potential for additive hypotension.
    Diazoxide: (Moderate) Additive hypotensive effects can occur with the concomitant administration of diazoxide with loop diuretics. This interaction can be therapeutically advantageous, but dosages must be adjusted accordingly. The manufacturer advises that IV diazoxide should not be administered to patients within 6 hours of receiving other antihypertensive agents.
    Dichlorphenamide: (Moderate) Use dichlorphenamide and diuretics together with caution. Dichlorphenamide increases potassium excretion and can cause hypokalemia and should be used cautiously with other drugs that may cause hypokalemia including loop diuretics and thiazide diuretics. Measure potassium concentrations at baseline and periodically during dichlorphenamide treatment. If hypokalemia occurs or persists, consider reducing the dose or discontinuing dichlorphenamide therapy.
    Diclofenac: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Diclofenac; Misoprostol: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Dicloxacillin: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Diethylpropion: (Major) Diethylpropion has vasopressor effects and may limit the benefit of loop diuretics. Although leading drug interaction texts differ in the potential for an interaction between diethylpropion and this group of antihypertensive agents, these effects are likely to be clinically significant and have been described in hypertensive patients on these medications.
    Diflunisal: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Digitoxin: (Moderate) Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics, increasing the risk of proarrhythmic effects of cardiac glycosides. Potassium levels should be monitored and normalized prior to and during concurrent diuretic administration and these agents.
    Digoxin: (Moderate) Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics, increasing the risk of proarrhythmic effects of cardiac glycosides. Potassium levels should be monitored and normalized prior to and during concurrent diuretic administration and these agents.
    Dihydrocodeine; Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Diphenhydramine; Hydrocodone; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Diphenhydramine; Ibuprofen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Diphenhydramine; Naproxen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Diphenhydramine; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Docusate Sodium; Senna: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Docusate: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Dofetilide: (Major) Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics increasing the potential for dofetilide-induced torsade de pointes. Potassium levels should be within the normal range prior and during administration of dofetilide.
    Dolasetron: (Major) The manufacturer warns that the coadministration of dolasetron with diuretics associated with hypokalemia could increase the risk of QT prolongation. Patients taking certain diuretics may develop an electrolyte abnormality that may lead to cardiac dysrhythmias and/or QT prolongation. Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics increasing the potential for cardiac arrhythmias. Potassium levels should be within the normal range prior to and during therapy with dolasetron.
    Doxacurium: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Droperidol: (Moderate) Caution is advised when using droperidol in combination with loop diuretics which may lead to electrolyte abnormalities, especially hypokalemia or hypomagnesemia, as such abnormalities may increase the risk for QT prolongation or cardiac arrhythmias.
    Dulaglutide: (Minor) Loop diuretics, such as bumetanide, furosemide, and torsemide, may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, including incretin mimetics. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Duloxetine: (Moderate) Patients receiving a diuretic during treatment with venlafaxine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH may occur during therapy with SNRIs, including venlafaxine. Cases involving serum sodium levels lower than 110 mmol/l have been reported. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of the SNRI should be considered in patients who develop symptomatic hyponatremia.
    Empagliflozin: (Moderate) When empagliflozin is initiated in patients already receiving loop diuretics, volume depletion can occur. Patients with impaired renal function, low systolic blood pressure, or who are elderly may also be at a greater risk for volume depletion and perhaps symptomatic hypotension. Before initiating empagliflozin in patients with one or more of these characteristics, volume status should be assessed and corrected. Monitor for signs and symptoms after initiating therapy. Loop diuretics can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. Patients receiving empagliflozin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary.
    Empagliflozin; Linagliptin: (Moderate) When empagliflozin is initiated in patients already receiving loop diuretics, volume depletion can occur. Patients with impaired renal function, low systolic blood pressure, or who are elderly may also be at a greater risk for volume depletion and perhaps symptomatic hypotension. Before initiating empagliflozin in patients with one or more of these characteristics, volume status should be assessed and corrected. Monitor for signs and symptoms after initiating therapy. Loop diuretics can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. Patients receiving empagliflozin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. (Minor) Loop diurectics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, such as linagliptin. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Empagliflozin; Metformin: (Moderate) When empagliflozin is initiated in patients already receiving loop diuretics, volume depletion can occur. Patients with impaired renal function, low systolic blood pressure, or who are elderly may also be at a greater risk for volume depletion and perhaps symptomatic hypotension. Before initiating empagliflozin in patients with one or more of these characteristics, volume status should be assessed and corrected. Monitor for signs and symptoms after initiating therapy. Loop diuretics can decrease the hypoglycemic effects of antidiabetic agents by producing an increase in blood glucose concentrations. Patients receiving empagliflozin should be monitored for changes in blood glucose control if such diuretics are added or deleted. Dosage adjustments may be necessary. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia.
    Enalapril, Enalaprilat: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Enalapril; Felodipine: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Enalapril; Hydrochlorothiazide, HCTZ: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Enflurane: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
    Ephedrine: (Major) The cardiovascular effects of sympathomimetics, such as ephedrine, may reduce the antihypertensive effects produced by loop diuretics. Blood pressure and heart rates should be monitored closely to confirm that the desired antihypertensive effect is achieved.
    Epoprostenol: (Moderate) Epoprostenol can have additive effects when administered with other antihypertensive agents. These effects can be used to therapeutic advantage, but dosage adjustments may be necessary.
    Eprosartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Eprosartan; Hydrochlorothiazide, HCTZ: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Escitalopram: (Moderate) Patients receiving a diuretic during treatment with escitalopram may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH has been reported during therapy with SSRIs. Cases involving serum sodium levels lower than 110 mmol/l have occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of escitalopram should be considered in patients who develop symptomatic hyponatremia.
    Esomeprazole: (Moderate) Proton pump inhibitors, such as esomeprazole, have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Esomeprazole; Naproxen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. (Moderate) Proton pump inhibitors, such as esomeprazole, have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Estradiol Cypionate; Medroxyprogesterone: (Minor) Estrogens can induce fluid retention and may increase blood pressure in some patients; patients who are receiving antihypertensive agents concurrently with hormone therapy should be monitored for antihypertensive effectiveness.
    Estradiol: (Minor) Estrogens can induce fluid retention and may increase blood pressure in some patients; patients who are receiving antihypertensive agents concurrently with hormone therapy should be monitored for antihypertensive effectiveness.
    Ethanol: (Moderate) Ethanol, since it also possesses diuretic properties, should be taken in small quantities in patients receiving loop diuretics. The diuretic properties may be additive, leading to dehydration in some patients. In addition, ethanol has hypotensive properties which can enhance the antihypertensive effects of diuretics.
    Etodolac: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Etomidate: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
    Exenatide: (Minor) Loop diuretics, such as bumetanide, furosemide, and torsemide, may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, including incretin mimetics. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Famotidine; Ibuprofen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Fenoprofen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Fentanyl: (Moderate) Fentanyl may reduce the efficacy of diuretics due to induction of the release of antidiuretic hormone. Adjustments to diuretic therapy may be needed in some patients. In addition, opiate agonists may potentiate orthostatic hypotension when used concurrently with diuretics.
    Fexofenadine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Fish Oil, Omega-3 Fatty Acids (Dietary Supplements): (Moderate) Co-enzyme Q10, ubiquinone (CoQ10) may lower blood pressure. CoQ10 use in combination with antihypertensive agents may lead to additional reductions in blood pressure in some individuals. Patients who choose to take CoQ10 concurrently with antihypertensive medications should receive periodic blood pressure monitoring. Patients should be advised to inform their prescriber of their use of CoQ10. (Moderate) High doses of fish oil supplements may produce a blood pressure lowering effect. It is possible that additive reductions in blood pressure may be seen when fish oils are used in a patient already taking antihypertensive agents.
    Fludrocortisone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Flunisolide: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Fluoxetine: (Moderate) Patients receiving a diuretic during treatment with fluoxetine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH has been reported during therapy with SSRIs. Cases involving serum sodium levels lower than 110 mmol/l have occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of fluoxetine should be considered in patients who develop symptomatic hyponatremia.
    Fluoxetine; Olanzapine: (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents. (Moderate) Patients receiving a diuretic during treatment with fluoxetine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH has been reported during therapy with SSRIs. Cases involving serum sodium levels lower than 110 mmol/l have occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of fluoxetine should be considered in patients who develop symptomatic hyponatremia.
    Flurbiprofen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Fluticasone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Fluticasone; Salmeterol: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Fluticasone; Umeclidinium; Vilanterol: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Fluticasone; Vilanterol: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Fluvoxamine: (Moderate) Patients receiving a diuretic during treatment with fluvoxamine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH has been reported during therapy with SSRIs. Cases involving serum sodium levels lower than 110 mmol/L have occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of fluvoxamine should be considered in patients who develop symptomatic hyponatremia.
    Formoterol; Mometasone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Foscarnet: (Moderate) Avoid concurrent use of loop diuretics with foscarnet. Coadministration may impair the renal tubular secretion of foscarnet, thereby increasing the possibility for toxicity. When use of a diuretic is indicated in patients being treated with foscarnet, consider a thiazide diuretic.
    Fosinopril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Fosinopril; Hydrochlorothiazide, HCTZ: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Fospropofol: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
    Gallium Ga 68 Dotatate: (Moderate) Mannitol can potentiate the effects of other diuretics when these drugs are administered concurrently.
    General anesthetics: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
    Gentamicin: (Moderate) The risk of ototoxicity or nephrotoxicity secondary to aminoglycosides may be increased by the addition of concomitant therapies with similar side effects, including loop diuretics. If loop diuretics and aminoglycosides are used together, it would be prudent to monitor renal function parameters, serum electrolytes, and serum aminoglycoside concentrations during therapy. Audiologic monitoring may be advisable during high dose therapy or therapy of long duration, when hearing loss is suspected, or in selected risk groups (e.g., neonates).
    Ginseng, Panax ginseng: (Major) Ginseng may decrease the effectiveness of loop diuretics. One case report described a temporal relationship between the use of ginseng and resistance to furosemide therapy, resulting in edema, hypertension, and hospitalization on 2 separate occasions. Other nutritional products were taken concurrently by the patient were not specified in the report. A mechanism of action or causal relationship has not been definitively established.
    Glimepiride: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Glimepiride; Pioglitazone: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Glimepiride; Rosiglitazone: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Glipizide: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Glipizide; Metformin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Glyburide: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Glyburide; Metformin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Granisetron: (Moderate) According to the manufacturer, caution is warranted when administering granisetron to patients with preexisting electrolyte abnormalities. Patients taking certain diuretics may develop an electrolyte abnormality that may lead to cardiac dysrhythmias and/or QT prolongation. Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics and thiazide diuretics, increasing the potential for cardiac arrhythmias.
    Guaifenesin; Hydrocodone; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Guaifenesin; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Guaifenesin; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Halofantrine: (Major) Due to the risks of cardiac toxicity of halofantrine in patients with hypokalemia and/or hypomagnesemia, the use of halofantrine should be avoided when feasible in those patients receiving potassium-wasting diuretic therapies such as loop diuretics.
    Haloperidol: (Major) QT prolongation has been observed during haloperidol treatment. Use of haloperidol and medications known to cause electrolyte imbalance may increase the risk of QT prolongation. Therefore, caution is advisable during concurrent use of haloperidol and loop diuretics. In general, haloperidol should also be used cautiously with antihypertensive agents due to the possibility of additive hypotension.
    Halothane: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
    Hawthorn, Crataegus laevigata: (Moderate) Hawthorn, Crataegus laevigata may lower peripheral vascular resistance. Hawthorn use in combination with antihypertensive agents may lead to additional reductions in blood pressure in some individuals. Patients receiving hawthorn concurrently with antihypertensive medications should receive periodic blood pressure monitoring.
    Hydralazine; Hydrochlorothiazide, HCTZ: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydralazine; Isosorbide Dinitrate, ISDN: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
    Hydrochlorothiazide, HCTZ: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Irbesartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Lisinopril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Losartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Methyldopa: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Metoprolol: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Moexipril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Olmesartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Propranolol: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Quinapril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Spironolactone: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Telmisartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Triamterene: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrochlorothiazide, HCTZ; Valsartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative. (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Hydrocodone; Ibuprofen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Hydrocodone; Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Hydrocodone; Potassium Guaiacolsulfonate; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Hydrocodone; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Hydrocortisone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Ibandronate: (Moderate) When the intravenous formulation of ibandronate is used for the treatment of hypercalcemia of malignancy, combination therapy with loop diuretics should be used with caution in order to avoid hypocalcemia. In patients with hypercalcemia of malignancy, the initial treatment typically includes the use of loop diuretics, in combination with saline hydration, however, diuretic therapy should not be employed prior to correction of hypovolemia and dehydration.
    Ibuprofen lysine: (Moderate) Ibuprofen lysine may reduce the effect of diuretics; diuretics can increase the risk of nephrotoxicity of NSAIDs in dehydrated patients. During coadministration of NSAIDs and diuretic therapy, patients should be monitored for changes in the effectiveness of their diuretic therapy and for signs and symptoms of renal impairment.
    Ibuprofen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Ibuprofen; Oxycodone: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Ibuprofen; Pseudoephedrine: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Ifosfamide: (Moderate) Nephrotoxic agents, such as the loop diuretics, can increase the nephrotoxicity of ifosfamide. Clinicians should be alert for an increased risk of ifosfamide toxicity, including neurotoxicity, kidney toxicity, and bone marrow suppression.
    Iloperidone: (Moderate) Secondary to alpha-blockade, iloperidone can produce vasodilation that may result in additive effects during concurrent use with antihypertensive agents. The potential reduction in blood pressure can precipitate orthostatic hypotension and associated dizziness, tachycardia, and syncope. If concurrent use of iloperidone and antihypertensive agents is necessary, patients should be counseled on measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning and rising slowly from a seated position. Close monitoring of blood pressure is recommended until the full effects of the combination therapy are known.
    Iloprost: (Moderate) Further reductions in blood pressure may occur when inhaled iloprost is administered to patients receiving other antihypertensive agents.
    Inamrinone: (Moderate) Hypokalemia may occur due to excessive diuresis during inamrinone therapy. Fluid and electrolyte changes and renal function should be carefully monitored during inamrinone therapy.
    Incretin Mimetics: (Minor) Loop diuretics, such as bumetanide, furosemide, and torsemide, may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, including incretin mimetics. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Indomethacin: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Insulin Degludec; Liraglutide: (Minor) Loop diuretics, such as bumetanide, furosemide, and torsemide, may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, including incretin mimetics. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Insulin Glargine; Lixisenatide: (Minor) Loop diuretics, such as bumetanide, furosemide, and torsemide, may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, including incretin mimetics. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Insulins: (Minor) Monitor patients receiving insulin closely for worsening glycemic control when bumetanide, furosemide, and torsemide are instituted. Bumetanide, furosemide, and torsemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents.
    Intravenous Lipid Emulsions: (Moderate) High doses of fish oil supplements may produce a blood pressure lowering effect. It is possible that additive reductions in blood pressure may be seen when fish oils are used in a patient already taking antihypertensive agents.
    Irbesartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Irinotecan: (Moderate) Volume depletion due to irinotecan-induced vomiting or diarrhea can be exacerbated by diuretics. Withholding diuretics during irinotecan dosing, especially during periods of active vomiting or diarrhea, may be desirable.
    Isocarboxazid: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with diuretics. Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider.
    Isoflurane: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
    Isoproterenol: (Moderate) The pharmacologic effects of isoproterenol may cause an increase in blood pressure. If isoproterenol is used concomitantly with antihypertensives, the blood pressure should be monitored as the administration of isoproterenol can compromise the effectiveness of antihypertensive agents.
    Isosorbide Dinitrate, ISDN: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
    Isosorbide Mononitrate: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
    Kanamycin: (Moderate) The risk of ototoxicity or nephrotoxicity secondary to aminoglycosides may be increased by the addition of concomitant therapies with similar side effects, including loop diuretics. If loop diuretics and aminoglycosides are used together, it would be prudent to monitor renal function parameters, serum electrolytes, and serum aminoglycoside concentrations during therapy. Audiologic monitoring may be advisable during high dose therapy or therapy of long duration, when hearing loss is suspected, or in selected risk groups (e.g., neonates).
    Ketamine: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
    Ketoprofen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Ketorolac: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Lactulose: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Lansoprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Lansoprazole; Naproxen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Levodopa: (Moderate) Concomitant use of antihypertensive agents with levodopa can result in additive hypotensive effects.
    Levomethadyl: (Moderate) Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics, increasing the risk of proarrhythmic effects of levomethadyl. Potassium levels should be monitored and normalized prior to and during concurrent diuretic administration and these agents.
    Levomilnacipran: (Moderate) Patients receiving a diuretic during treatment with venlafaxine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH may occur during therapy with SNRIs, including venlafaxine. Cases involving serum sodium levels lower than 110 mmol/l have been reported. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of the SNRI should be considered in patients who develop symptomatic hyponatremia.
    Levothyroxine: (Moderate) Use high doses (more than 80 mg) of furosemide and thyroid hormones together with caution. High doses of furosemide may inhibit the binding of thyroid hormones to carrier proteins, resulting in a transient increase in free thyroid hormones followed by an overall decrease in total thyroid hormone concentrations.
    Linagliptin: (Minor) Loop diurectics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, such as linagliptin. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Linagliptin; Metformin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. (Minor) Loop diurectics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, such as linagliptin. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Liothyronine: (Moderate) Use high doses (more than 80 mg) of furosemide and thyroid hormones together with caution. High doses of furosemide may inhibit the binding of thyroid hormones to carrier proteins, resulting in a transient increase in free thyroid hormones followed by an overall decrease in total thyroid hormone concentrations.
    Liotrix: (Moderate) Use high doses (more than 80 mg) of furosemide and thyroid hormones together with caution. High doses of furosemide may inhibit the binding of thyroid hormones to carrier proteins, resulting in a transient increase in free thyroid hormones followed by an overall decrease in total thyroid hormone concentrations.
    Liraglutide: (Minor) Loop diuretics, such as bumetanide, furosemide, and torsemide, may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, including incretin mimetics. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Lisdexamfetamine: (Major) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents. Close monitoring of blood pressure or the selection of alternative therapeutic agents may be needed.
    Lisinopril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Lithium: (Moderate) Loop diuretics may increase serum lithium concentrations by increasing lithium reabsorption in the proximal tubule, and possibly by decreasing lithium reabsorption in the loop of Henle with an increase in lithium delivery to the distal tubule with minor compensatory reabsorption. However, the effect of loop diuretics on lithium clearance relative to thiazide diuretics is generally minor. In one small study evaluating the pharmacokinetic effects of several different medications on a single 600 mg dose of lithium carbonate, administration of furosemide resulted in an 11% decrease in lithium clearance. According to the Beers Criteria, concurrent use of lithium and loop diuretics may result in a clinically important drug interaction, particularly in older adults. The Beers expert panel recommends avoiding concurrent use due to an increased risk of lithium toxicity. If the combination is necessary, monitoring of lithium concentrations is recommended.
    Lixisenatide: (Minor) Loop diuretics, such as bumetanide, furosemide, and torsemide, may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents, including incretin mimetics. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Loratadine; Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Losartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Lovastatin; Niacin: (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents. This effect is of particular concern in the setting of acute myocardial infarction, unstable angina, or other acute hemodynamic compromise.
    Lubiprostone: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Lurasidone: (Moderate) Due to the antagonism of lurasidone at alpha-1 adrenergic receptors, the drug may enhance the hypotensive effects of alpha-blockers and other antihypertensive agents. If concurrent use of lurasidone and antihypertensive agents is necessary, patients should be counseled on measures to prevent orthostatic hypotension, such as sitting on the edge of the bed for several minutes prior to standing in the morning and rising slowly from a seated position. Close monitoring of blood pressure is recommended until the full effects of the combination therapy are known.
    Magnesium Citrate: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Magnesium Hydroxide: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Magnesium Salts: (Moderate) Diuretics may interfere with the kidneys ability to regulate magnesium concentrations. Long-term use of diuretics may impair the magnesium-conserving ability of the kidneys and lead to hypomagnesemia. (Moderate) Diuretics may interfere with the kidneys ability to regulate magnesium concentrations. Long-term use of loop diuretics may impair the magnesium-conserving ability of the kidneys and lead to hypomagnesemia. In addition, use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as diuretics.
    Magnesium Sulfate; Potassium Sulfate; Sodium Sulfate: (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as diuretics.
    Mannitol: (Moderate) Mannitol can potentiate the effects of other diuretics when these drugs are administered concurrently.
    Meclofenamate Sodium: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Mefenamic Acid: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Meglitinides: (Minor) Loop diuretics have been associated with hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between loop diuretics and all antidiabetic agents. Monitor for a loss of diabetic control.
    Meloxicam: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Mestranol; Norethindrone: (Minor) Estrogen containing oral contraceptives can induce fluid retention and may increase blood pressure in some patients; monitor patients receiving concurrent therapy to confirm that the desired antihypertensive effect is being obtained.
    Metformin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia.
    Metformin; Pioglitazone: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Metformin; Repaglinide: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. (Minor) Loop diuretics have been associated with hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between loop diuretics and all antidiabetic agents. Monitor for a loss of diabetic control.
    Metformin; Rosiglitazone: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Metformin; Saxagliptin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Metformin; Sitagliptin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Methadone: (Moderate) Diuretics can cause electrolyte disturbances such as hypomagnesemia and hypokalemia, which may prolong the QT interval. As methadone may also prolong the QT interval, cautious coadministration with diuretics is needed.
    Methamphetamine: (Major) Amphetamines increase both systolic and diastolic blood pressure and may counteract the activity of some antihypertensive agents, such as loop diuretics. Close monitoring of blood pressure or the selection of alternative therapeutic agents may be needed.
    Methazolamide: (Moderate) Loop diuretics may increase the risk of hypokalemia if used concurrently with methazolamide. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy. There may also be an additive diuretic or hyperuricemic effect.
    Methohexital: (Moderate) Concurrent use of methohexital and antihypertensive agents increases the risk of developing hypotension.
    Methotrexate: (Moderate) Furosemide undergoes significant renal tubular secretion. Concomitant administration of furosemide with other drugs that undergo significant renal tubular secretion, such as methotrexate, may result in decreased effect of furosemide and, conversely, decreased elimination of the other drug. High dose treatment of both furosemide and other drugs that undergo renal tubular secretion may result in increased toxicity of both drugs.
    Methyclothiazide: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Methylcellulose: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Methylphenidate: (Moderate) Methylphenidate can reduce the hypotensive effect of antihypertensive agents such as loop diuretics. Periodic evaluation of blood pressure is advisable during concurrent use of methylphenidate and antihypertensive agents, particularly during initial coadministration and after dosage increases of methylphenidate.
    Methylprednisolone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Metolazone: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Miglitol: (Minor) Loop diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Milnacipran: (Moderate) Patients receiving a diuretic during treatment with venlafaxine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH may occur during therapy with SNRIs, including venlafaxine. Cases involving serum sodium levels lower than 110 mmol/l have been reported. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of the SNRI should be considered in patients who develop symptomatic hyponatremia.
    Milrinone: (Moderate) Concurrent administration of antihypertensive agents could lead to additive hypotension when administered with milrinone. Titrate milrinone dosage according to hemodynamic response.
    Mineral Oil: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Mirtazapine: (Moderate) Hyponatremia has been reported very rarely during mirtazapine administration. Caution is advisable in patients receiving medications known to cause hyponatremia, such as diuretics. Hyponatremia may manifest as headache, difficulty concentrating, memory impairment, confusion, weakness, and unsteadiness which may result in falls. Severe manifestations include hallucinations, syncope, seizure, coma, respiratory arrest, and death. Symptomatic hyponatremia may require discontinuation of mirtazapine, as well as implementation of the appropriate medical interventions.
    Mivacurium: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Moexipril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Mometasone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Morphine: (Moderate) Morphine may reduce the efficacy of diuretics due to induction of the release of antidiuretic hormone. Morphine may also cause acute urinary retention by causing a spasm of the bladder sphincter; men with enlarged prostates may have a higher risk of this reaction.
    Morphine; Naltrexone: (Moderate) Morphine may reduce the efficacy of diuretics due to induction of the release of antidiuretic hormone. Morphine may also cause acute urinary retention by causing a spasm of the bladder sphincter; men with enlarged prostates may have a higher risk of this reaction.
    Nabumetone: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Nafcillin: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Naproxen: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Naproxen; Pseudoephedrine: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain. (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Naproxen; Sumatriptan: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Nateglinide: (Minor) Loop diuretics have been associated with hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between loop diuretics and all antidiabetic agents. Monitor for a loss of diabetic control.
    Nebivolol; Valsartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Nefazodone: (Minor) Although relatively infrequent, nefazodone may cause orthostatic hypotension in some patients; this effect may be additive with antihypertensive agents. Blood pressure monitoring and dosage adjustments of either drug may be necessary.
    Nesiritide, BNP: (Major) The potential for hypotension may be increased when coadministering nesiritide with antihypertensive agents.
    Neuromuscular blockers: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Niacin, Niacinamide: (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents. This effect is of particular concern in the setting of acute myocardial infarction, unstable angina, or other acute hemodynamic compromise.
    Niacin; Simvastatin: (Moderate) Cutaneous vasodilation induced by niacin may become problematic if high-dose niacin is used concomitantly with other antihypertensive agents. This effect is of particular concern in the setting of acute myocardial infarction, unstable angina, or other acute hemodynamic compromise.
    Nitrates: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
    Nitroglycerin: (Moderate) Concomitant use of nitrates with other antihypertensive agents can cause additive hypotensive effects. Dosage adjustments may be necessary.
    Nitroprusside: (Moderate) Additive hypotensive effects may occur when nitroprusside is used concomitantly with other antihypertensive agents. Dosages should be adjusted carefully, according to blood pressure.
    Non-Ionic Contrast Media: (Moderate) Because patients should be well-hydrated prior to the administration of contrast media, loop diuretics such as furosemide that cause intravascular volume depletion might increase the risk of nephrotoxicity when using radiopaque contrast agents. In addition, furosemide plus normal saline have been evaluated for the prevention of contrast induced nephropathy; in one retrospective review, the incidence of contrast-induced nephropathy in the furosemide plus saline group was almost four times that of the saline only group (40% versus 11%, respectively). Other studies have shown no benefit with combination therapy.
    Norepinephrine: (Moderate) Diuretics can cause decreased arterial responsiveness to norepinephrine, but the effect is not sufficient to preclude their coadministration.
    Octreotide: (Moderate) Patients receiving diuretics or other agents to control fluid and electrolyte balance may require dosage adjustments while receiving octreotide due to additive effects.
    Olanzapine: (Moderate) Olanzapine may induce orthostatic hypotension and thus enhance the effects of antihypertensive agents.
    Olmesartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Ombitasvir; Paritaprevir; Ritonavir: (Moderate) The manufacturer of dasabuvir; ombitasvir; paritaprevir; ritonavir and ombitasvir; paritaprevir; ritonavir recommends caution and clinical monitoring if administered concurrently with furosemide. Use of these drugs in combination has resulted in elevated furosemide maximum plasma concentrations (Cmax). Individualize the dose of furosemide based on the patient's clinical response. The dose should be re-adjusted after completion of the hepatitis C treatment regimen.
    Omeprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Omeprazole; Sodium Bicarbonate: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Ondansetron: (Moderate) The coadministration of ondansetron with diuretics associated with hypokalemia could increase the risk of QT prolongation. Potassium levels should be within the normal range prior to and during therapy with ondansetron.
    Oprelvekin, rh-IL-11: (Major) Patients receiving loop diuretics during oprelvekin, rh-IL-11 therapy are at increased risk for developing severe hypokalemia; close monitoring of fluid and electrolyte status is warranted during concurrent diuretic and oprelvekin therapy.
    Oxacillin: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Oxaprozin: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Oxybutynin: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms.
    Oxymetazoline: (Major) The vasoconstricting actions of oxymetazoline, an alpha adrenergic agonist, may reduce the antihypertensive effects produced by diuretics. If these drugs are used together, closely monitor for changes in blood pressure.
    Paliperidone: (Moderate) Paliperidone may cause orthostatic hypotension and thus enhance the hypotensive effects of antihypertensive agents. Lower initial doses of paliperidone may be necessary in patients receiving antihypertensive agents concomitantly.
    Pamidronate: (Moderate) Because both loop diuretics and intravenously administered bisphosphonates (i.e., alendronate, ibandronate, pamidronate, and zoledronic acid) can cause a decrease in serum calcium, caution is advised when used concomitantly in the treatment of hypercalcemia of malignancy in order to avoid hypocalcemia. In patients with hypercalcemia of malignancy, the initial treatment typically includes the use of loop diuretics, in combination with saline hydration, however, diuretic therapy should not be employed prior to correction of hypovolemia and dehydration.
    Pancuronium: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Pantoprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Paromomycin: (Moderate) The risk of ototoxicity or nephrotoxicity secondary to aminoglycosides may be increased by the addition of concomitant therapies with similar side effects, including loop diuretics. If loop diuretics and aminoglycosides are used together, it would be prudent to monitor renal function parameters, serum electrolytes, and serum aminoglycoside concentrations during therapy. Audiologic monitoring may be advisable during high dose therapy or therapy of long duration, when hearing loss is suspected, or in selected risk groups (e.g., neonates).
    Paroxetine: (Moderate) Patients receiving a diuretic during treatment with paroxetine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH has been reported during therapy with SSRIs. Cases involving serum sodium levels lower than 110 mmol/l have occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of paroxetine should be considered in patients who develop symptomatic hyponatremia.
    Pasireotide: (Major) Cautious use of pasireotide and medicines that can affect potassium or magnesium concentrations such as diuretics is advised. Pasireotide may prolong the QT interval, and hypokalemia and/or hypomagnesemia are risk factors for QT prolongation. Assess the patient's potassium and magnesium concentration before and periodically during pasireotide receipt. Correct hypokalemia and hypomagnesemia before pasireotide receipt.
    Penicillin G Benzathine: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Penicillin G Benzathine; Penicillin G Procaine: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Penicillin G Procaine: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Penicillin G: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Penicillin V: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Penicillins: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Pentamidine: (Major) Drugs that are associated with hypokalemia and/or hypomagnesemia such as loop diuretics should be used with caution in patients also receiving pentamidine. Since pentamidine may cause QT prolongation independently of electrolyte imbalances, the risk for cardiac arrhythmias is potentiated by the concomitant use of agents associated with electrolyte loss. .
    Pentoxifylline: (Moderate) Pentoxifylline has been used concurrently with antihypertensive drugs (beta blockers, diuretics) without observed problems. Small decreases in blood pressure have been observed in some patients treated with pentoxifylline; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensives. If indicated, dosage of the antihypertensive agents should be reduced.
    Perindopril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Perindopril; Amlodipine: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Phenelzine: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with diuretics. Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider.
    Phentermine; Topiramate: (Moderate) Topiramate is a carbonic anhydrase inhibitor. Concurrent use of topiramate with non-potassium sparing diuretics (e.g., loop diuretics) may potentiate the potassium-wasting action of these diuretics. Monitor baseline and periodic potassium concentrations during coadministration.
    Phenylephrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Phenylephrine; Promethazine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving decongestant sympathomimetics at recommended doses do not appear at high risk for significant elevations in blood pressure, however, increased blood pressure has been reported in some patients.
    Phenytoin: (Moderate) Limited clinical data suggest that phenytoin can interfere with the clinical response to furosemide. Phenytoin has been shown to decrease furosemide oral bioavailability by up to 50 percent without affecting its systemic clearance.
    Pimozide: (Major) Pimozide is associated with a well-established risk of QT prolongation and torsade de pointes (TdP). Use of pimozide and medications known to cause electrolyte imbalance may increase the risk of QT prolongation. Therefore, caution is advisable during concurrent use of pimozide and loop diuretics. According to the manufacturer, potassium deficiencies should be correctly prior to treatment with pimozide and normalized potassium levels should be maintained during treatment.
    Pioglitazone: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Piperacillin: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Piperacillin; Tazobactam: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Piroxicam: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Polycarbophil: (Moderate) Loop diuretics may increase the risk of hypokalemia, especially in patients receiving prolonged therapy with laxatives such as calcium polycarbophil. Monitor serum potassium to determine the need for potassium supplementation and/or alteration in drug therapy.
    Polyethylene Glycol: (Moderate) There have been rare reports of generalized tonic-clonic seizures associated with electrolyte abnormalities in patients using polyethylene glycol colon preparation products. In addition, there have been rare reports of serious arrhythmias associated with the use of ionic osmotic laxative products for bowel preparation. Some of these events are associated with electrolyte imbalance. Therefore, polyethylene glycol; electrolytes preparations should be used with caution in patients using concomitant medications that increase the risk of electrolyte abnormalities such as loop diuretics.
    Polyethylene Glycol; Electrolytes: (Moderate) There have been rare reports of generalized tonic-clonic seizures associated with electrolyte abnormalities in patients using polyethylene glycol colon preparation products. In addition, there have been rare reports of serious arrhythmias associated with the use of ionic osmotic laxative products for bowel preparation. Some of these events are associated with electrolyte imbalance. Therefore, polyethylene glycol; electrolytes preparations should be used with caution in patients using concomitant medications that increase the risk of electrolyte abnormalities such as loop diuretics. (Moderate) Use caution when prescribing sulfate salt bowel preparation in patients taking concomitant medications that may affect renal function such as diuretics.
    Polyethylene Glycol; Electrolytes; Bisacodyl: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy. (Moderate) There have been rare reports of generalized tonic-clonic seizures associated with electrolyte abnormalities in patients using polyethylene glycol colon preparation products. In addition, there have been rare reports of serious arrhythmias associated with the use of ionic osmotic laxative products for bowel preparation. Some of these events are associated with electrolyte imbalance. Therefore, polyethylene glycol; electrolytes preparations should be used with caution in patients using concomitant medications that increase the risk of electrolyte abnormalities such as loop diuretics.
    Polymyxin B: (Moderate) Systemic polymyxin B is nephrotoxic and should be used cautiously with loop diuretics, which may cause azotemia and may increase the risk for renal toxicity when coadministered. Close monitoring of renal status and for drug toxicity is recommended. Diminishing urine output and a rising BUN are indications to discontinue systemic polymyxin B therapy.
    Pramlintide: (Minor) Loop diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents. Monitor patient for diabetic control.
    Prazosin: (Moderate) Prazosin is well-known to produce a 'first-dose' phenomenon. Some patients develop significant hypotension shortly after administration of the first dose. The first dose response (acute postural hypotension) of prazosin may be exaggerated in patients who are receiving beta-adrenergic blockers, diuretics, or other antihypertensive agents. Concomitant administration of prazosin with other antihypertensive agents is not prohibited, however. This can be therapeutically advantageous, but lower dosages of each agent should be used.
    Prednisolone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Prednisone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Probenecid: (Moderate) Probenecid can interfere with the natriuresis and plasma renin activity increases caused by diuretics such as furosemide. Furosemide can in turn increase the levels of serum uric acid, antagonizing the effects of probenecid.
    Procainamide: (Moderate) Procainamide can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents. Intravenous administration of procainamide is more likely to cause hypotensive effects.
    Procaine: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents.
    Propofol: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
    Pseudoephedrine: (Moderate) The cardiovascular effects of sympathomimetics may reduce the antihypertensive effects produced by diuretics. Well-controlled hypertensive patients receiving pseudoephedrine at recommended doses do not appear at high risk for significant elevations in blood pressure; however, increased blood pressure (especially systolic hypertension) has been reported in some patients.
    Psyllium: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Quetiapine: (Major) QT prolongation has occurred during concurrent use of quetiapine and medications known to cause electrolyte imbalance. Therefore, caution is advisable during concurrent use of quetiapine and loop diuretics.
    Quinapril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Quinidine: (Moderate) Quinidine can decrease blood pressure and should be used cautiously in patients receiving antihypertensive agents due to the potential for additive hypotension.
    Rabeprazole: (Moderate) Proton pump inhibitors have been associated with hypomagnesemia. Hypomagnesemia occurs with loop diuretics (furosemide, bumetanide, torsemide, and ethacrynic acid). Low serum magnesium may lead to serious adverse events such as muscle spasm, seizures, and arrhythmias. Therefore, clinicians should monitor serum magnesium concentrations periodically in patients taking a PPI and diuretics concomitantly. Patients who develop hypomagnesemia may require PPI discontinuation in addition to magnesium replacement.
    Ramipril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Rapacuronium: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Rasagiline: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with diuretics. Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider.
    Repaglinide: (Minor) Loop diuretics have been associated with hyperglycemia. Because of this, a potential pharmacodynamic interaction exists between loop diuretics and all antidiabetic agents. Monitor for a loss of diabetic control.
    Risperidone: (Major) Risperidone may induce orthostatic hypotension and thus enhance the hypotensive effects of antihypertensive agents. Lower initial doses or slower dose titration of risperidone may be necessary in patients receiving antihypertensive agents concomitantly. Furthermore, two of four placebo-controlled trials showed that elderly patients with dementia-related psychosis receiving the combination of risperidone and furosemide had a higher incidence of mortality than those receiving either agent alone. The mechanism for this adverse association is unknown. Caution should be exercised when the combined use of risperidone and furosemide is necessary in those with dementia-related psychosis.
    Rocuronium: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Rofecoxib: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Rosiglitazone: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Sacubitril; Valsartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Salicylates: (Moderate) Salicylates may decrease the diuretic, natriuretic, and antihypertensive actions of diuretics, possibly through inhibition of renal prostaglandin synthesis. Patients receiving loop diuretics and salicylates should be monitored for changes in the effectiveness of their diuretic therapy.
    Saxagliptin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Selegiline: (Moderate) Additive hypotensive effects may be seen when monoamine oxidase inhibitors (MAOIs) are combined with antihypertensives. Careful monitoring of blood pressure is suggested during concurrent therapy of MAOIs with diuretics. Patients should be instructed to rise slowly from a sitting position, and to report syncope or changes in blood pressure or heart rate to their health care provider.
    Senna: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Serotonin norepinephrine reuptake inhibitors: (Moderate) Patients receiving a diuretic during treatment with venlafaxine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH may occur during therapy with SNRIs, including venlafaxine. Cases involving serum sodium levels lower than 110 mmol/l have been reported. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of the SNRI should be considered in patients who develop symptomatic hyponatremia.
    Sertraline: (Moderate) Patients receiving a diuretic during treatment with sertraline may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH has been reported during therapy with SSRIs. Cases involving serum sodium levels lower than 110 mmol/l have occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of sertraline should be considered in patients who develop symptomatic hyponatremia.
    Sevoflurane: (Moderate) General anesthetics can potentiate the hypotensive effects of antihypertensive agents.
    Silodosin: (Moderate) During clinical trials with silodosin, the incidence of dizziness and orthostatic hypotension was higher in patients receiving concomitant antihypertensive treatment. Thus, caution is advisable when silodosin is administered with antihypertensive agents.
    Simvastatin; Sitagliptin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Sitagliptin: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between these drugs and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely if these drugs are initiated.
    Sodium Phosphate Monobasic Monohydrate; Sodium Phosphate Dibasic Anhydrous: (Moderate) Concomitant use of medicines with potential to alter renal perfusion or function such as diuretics, may increase the risk of acute phosphate nephropathy in patients receiving sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous. In addition, loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Sodium picosulfate; Magnesium oxide; Anhydrous citric acid: (Moderate) Use caution when prescribing sodium picosulfate; magnesium oxide; anhydrous citric acid in patients taking concomitant medications that may affect renal function such as diuretics. In addition, use caution in patients receiving drugs where hypokalemia is a particular risk.
    Sodium Polystyrene Sulfonate: (Moderate) Sodium polystyrene sulfonate should be used cautiously with other agents that can induce hypokalemia such as loop diuretics, insulins, or intravenous sodium bicarbonate. Because of differences in onset of action, sodium polystyrene sulfonate is often used with these agents. With appropriate monitoring, hypokalemia can be avoided.
    Solifenacin: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms. Risk versus benefit should be addressed in patients receiving diuretics and solifenacin.
    Sorbitol: (Moderate) Loop diuretics may increase the risk of hypokalemia especially in patients receiving prolonged therapy with laxatives. Monitor serum potassium levels to determine the need for potassium supplementation and/or alteration in drug therapy.
    Streptomycin: (Moderate) The risk of ototoxicity or nephrotoxicity secondary to aminoglycosides may be increased by the addition of concomitant therapies with similar side effects, including loop diuretics. If loop diuretics and aminoglycosides are used together, it would be prudent to monitor renal function parameters, serum electrolytes, and serum aminoglycoside concentrations during therapy. Audiologic monitoring may be advisable during high dose therapy or therapy of long duration, when hearing loss is suspected, or in selected risk groups (e.g., neonates).
    Streptozocin: (Minor) Because streptozocin is nephrotoxic, concurrent or subsequent administration of other nephrotoxic agents (e.g,. aminoglycosides, amphotericin B, cisplatin, foscarnet, or diuretics) could exacerbate the renal insult.
    Succinylcholine: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Sucralfate: (Major) According to the manufacturer for furosemide, simultaneous administration of sucralfate and furosemide may reduce its natriuretic and antihypertensive effects. Patients receiving both drugs should be observed closely to determine if the desired diuretic and/or antihypertensive effect of furosemide is achieved. The intake of furosemide and sucralfate is recommended to be separated by at least two hours.
    Sulfonylureas: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Sulindac: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Telavancin: (Moderate) Concurrent or sequential use of telavancin with other potentially nephrotoxic drugs such as loop diuretics may lead to additive nephrotoxicity. Closely monitor renal function and adjust telavancin doses based on calculated creatinine clearance.
    Telmisartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Teriflunomide: (Moderate) Teriflunomide is an inhibitor of the renal uptake organic anion transporter OAT3. Use of teriflunomide with furosemide, a substrate of OAT3, may increase furosemide plasma concentrations. Monitor for increased adverse effects from furosemide, such as excessive fluid loss or hypotension.
    Tetracaine: (Moderate) Local anesthetics may cause additive hypotension in combination with antihypertensive agents. Use extreme caution with the concomitant use of tetracaine and antihypertensive agents.
    Thiazide diuretics: (Moderate) Concomitant use of a thiazide diuretiic, or the related drug metolazone, with a loop diuretic can cause additive electrolyte and fluid loss. In patients with creatinine clearances > 30 ml/min, the combinations may also lead to profound fluid and electrolyte loss in some patients. Thus, use cautiously and with monitoring of renal function, blood pressure, cardiac status, electrolytes (especially potassium), and monitor the clinical response for the condition treated.
    Thiazolidinediones: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus, probably due to diuretic-induced hypokalemia. Because of this, a potential pharmacodynamic interaction exists between furosemide and all antidiabetic agents. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Thiopental: (Moderate) Concurrent use of thiopental and alpha-blockers or antihypertensive agents increases the risk of developing hypotension.
    Thiothixene: (Moderate) Thiothixene should be used cautiously in patients receiving antihypertensive agents. Additive hypotensive effects are possible.
    Thyroid hormones: (Moderate) Use high doses (more than 80 mg) of furosemide and thyroid hormones together with caution. High doses of furosemide may inhibit the binding of thyroid hormones to carrier proteins, resulting in a transient increase in free thyroid hormones followed by an overall decrease in total thyroid hormone concentrations.
    Ticarcillin: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Ticarcillin; Clavulanic Acid: (Minor) Furosemide may compete with penicillin for renal tubular secretion, increasing penicillin serum concentrations. This combination should be used with caution and patients monitored for increased side effects.
    Tizanidine: (Moderate) Concurrent use of tizanidine with antihypertensive agents can result in significant hypotension. Caution is advised when tizanidine is to be used in patients receiving concurrent antihypertensive therapy.
    Tobramycin: (Moderate) The risk of ototoxicity or nephrotoxicity secondary to aminoglycosides may be increased by the addition of concomitant therapies with similar side effects, including loop diuretics. If loop diuretics and aminoglycosides are used together, it would be prudent to monitor renal function parameters, serum electrolytes, and serum aminoglycoside concentrations during therapy. Audiologic monitoring may be advisable during high dose therapy or therapy of long duration, when hearing loss is suspected, or in selected risk groups (e.g., neonates).
    Tolazamide: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Tolbutamide: (Minor) Furosemide may cause hyperglycemia and glycosuria in patients with diabetes mellitus. This interference can lead to a loss of diabetic control, so diabetic patients should be monitored closely.
    Tolmetin: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Tolterodine: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms.
    Tolvaptan: (Moderate) Monitor serum sodium closely if these drugs are used together. Coadministration of tolvaptan and loop diuretics increases the risk of too rapid correction of serum sodium.
    Topiramate: (Moderate) Topiramate is a carbonic anhydrase inhibitor. Concurrent use of topiramate with non-potassium sparing diuretics (e.g., loop diuretics) may potentiate the potassium-wasting action of these diuretics. Monitor baseline and periodic potassium concentrations during coadministration.
    Trandolapril: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Trandolapril; Verapamil: (Moderate) Coadministration of loop diuretics and Angiotensin-converting enzyme inhibitors (ACE inhibitors) may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Tranylcypromine: (Severe) The use of hypotensive agents and tranylcypromine is contraindicated by the manufacturer of tranylcypromine because the effects of hypotensive agents may be markedly potentiated.
    Trazodone: (Minor) Due to additive hypotensive effects, patients receiving antihypertensive agents concurrently with trazodone may have excessive hypotension. Decreased dosage of the antihypertensive agent may be required when given with trazodone.
    Triamcinolone: (Moderate) Corticosteroids may accentuate the electrolyte loss associated with diuretic therapy resulting in hypokalemia and/or hypomagnesemia. While glucocorticoids with mineralocorticoid activity (e.g., cortisone, hydrocortisone) can cause sodium and fluid retention. Close monitoring of electrolytes should occur in patients receiving these drugs concomitantly.
    Trospium: (Minor) Diuretics can increase urinary frequency, which may aggravate bladder symptoms.
    Tubocurarine: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Valdecoxib: (Moderate) If a nonsteroidal anti-inflammatory drug (NSAID) and a diuretic are used concurrently, carefully monitor the patient for signs and symptoms of decreased renal function and diuretic efficacy. Patients taking diuretics and NSAIDs concurrently are at higher risk of developing renal insufficiency. NSAIDs may reduce the natriuretic effect of diuretics in some patients. NSAIDs have been associated with an inhibition of prostaglandin synthesis, which may result in reduced renal blood flow leading to renal insufficiency and increases in blood pressure that are often accompanied by peripheral edema and weight gain.
    Valsartan: (Moderate) Coadministration of furosemide and Angiotensin-converting enzyme inhibitors (ACE inhibitors) or angiotensin II receptor antagonists may result in severe hypotension and deterioration in renal function, including renal failure. Hyponatremia or hypovolemia predisposes patients to acute hypotensive episodes following initiation of ACE inhibitor therapy. While ACE inhibitors and loop diuretics are routinely administered together in the treatment of heart failure, if an ACE inhibitor is to be administered to a patient receiving furosemide, initial doses should be conservative.
    Vancomycin: (Moderate) Vancomycin should be used cautiously with other ototoxic drugs such as furosemide.
    Vecuronium: (Moderate) Furosemide-induced hypokalemia can potentiate neuromuscular blockade with nondepolarizing neuromuscular blockers. In addition, furosemide may antagonize the skeletal muscle relaxing effect of tubocurarine and can potentiate neuromuscular blockade following succinylcholine administration.
    Venlafaxine: (Moderate) Patients receiving a diuretic during treatment with venlafaxine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Hyponatremia due to SIADH may occur during therapy with SNRIs, including venlafaxine. Cases involving serum sodium levels lower than 110 mmol/l have been reported. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of the SNRI should be considered in patients who develop symptomatic hyponatremia.
    Vilazodone: (Moderate) Patients receiving vilazodone with medications known to cause hyponatremia, such as diuretics, may be at increased risk of developing hyponatremia. Hyponatremia has occurred in association with the use of antidepressants such as selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), and mirtazapine. Hyponatremia may manifest as headache, difficulty concentrating, memory impairment, confusion, weakness, and unsteadiness which may result in falls. Severe manifestations include hallucinations, syncope, seizure, coma, respiratory arrest, and death. Symptomatic hyponatremia may require discontinuation of vilazodone, as well as implementation of the appropriate medical interventions.
    Vorinostat: (Moderate) Use vorinostat and loop diuretics together with caution; the risk of QT prolongation and arrhythmias may be increased if electrolyte abnormalities occur. Loop diuretics may cause electrolyte imbalances including low potassium; hypomagnesemia, hypokalemia, or hypocalcemia may increase the risk of QT prolongation with vorinostat. Frequently monitor serum electrolytes if concomitant use of these drugs is necessary.
    Vortioxetine: (Moderate) Patients receiving a diuretic during treatment with vortioxetine may be at greater risk of developing syndrome of inappropriate antidiuretic hormone secretion (SIADH). Clinically significant hyponatremia has been reported during therapy with vortioxetine. One case involving serum sodium levels lower than 110 mmol/l has occurred. Hyponatremia may be potentiated by agents which can cause sodium depletion such as diuretics. Discontinuation of vortioxetine should be considered in patients who develop symptomatic hyponatremia.
    Warfarin: (Minor) Per the prescribing information for warfarin sodium, concomitant use of diuretics (carbonic anhydrase inhibitors, loop diuretics, osmotic diuretics, potassium-sparing diuretics, and thiazide diuretics) and warfarin may result in an increased or decreased PT/INR. Patients should be monitored for changes in the INR when either of these drugs is initiated or discontinued, or if the dosage is changed.
    Yohimbine: (Moderate) Yohimbine can increase blood pressure and therefore can antagonize the therapeutic action of antihypertensive agents. Use with particular caution in hypertensive patients with high or uncontrolled BP.
    Ziconotide: (Moderate) Patients taking diuretics with ziconotide may be at higher risk of depressed levels of consciousness. If altered consciousness occurs, consideration of diuretic cessation is warranted in addition to ziconotide discontinuation.
    Ziprasidone: (Minor) Monitor of potassium and magnesium levels when loop diuretics are used during ziprasidone therapy. The risk of QT prolongation from ziprasidone is increased in the presence of hypokalemia or hypomagnesemia.
    Zoledronic Acid: (Moderate) Loop diuretics should be used with caution in combination with zoledronic acid in order to avoid hypocalcemia. In patients with hypercalcemia of malignancy, the initial treatment typically includes the use of loop diuretics, in combination with saline hydration, however, diuretic therapy should not be employed prior to correction of hypovolemia and dehydration.

    PREGNANCY AND LACTATION

    Pregnancy

    According to the manufacturer, because furosemide appears in breast milk, caution should be exercised when furosemide is administered to a breast-feeding mother. In addition, diuretics such as furosemide may suppress lactation as a result of intense diuresis. Of note, the use of bendroflumethiazide, chlorthalidone, chlorothiazide, and hydrochlorothiazide is considered to be usually compatible with breast-feeding by the American Academy of Pediatrics, due to lack of noted adverse effects on the nursing infant. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally ingested drug, healthcare providers are encouraged to report the adverse effect to the FDA.

    MECHANISM OF ACTION

    Furosemide is a loop diuretic that inhibits sodium and chloride resorption by competing with chloride for the Na+/K+/2Cl- co-transporter in the ascending limb of the loop of Henle. The manufacturer also states that furosemide inhibits the absorption of sodium and chloride in the proximal and distal tubules. A profound diuresis results from the increased urinary excretion of sodium, chloride, potassium, and hydrogen ions. In addition, furosemide increases the excretion of calcium, magnesium, bicarbonate, ammonium, and phosphate. The diuresis caused by furosemide can lead to increased aldosterone production, resulting in increased sodium resorption, and increased potassium and hydrogen excretion. Excessive loss of these electrolytes can lead to metabolic alkalosis.
     
    Furosemide's effectiveness is independent of the acid-base status of the patient. Renal vasodilation occurs following administration of furosemide; renal vascular resistance decreases, and renal blood flow is enhanced. Reduced peripheral vascular resistance and increased peripheral venous capacitance also occur, and the subsequent decrease in left ventricular filling pressure may contribute to the drug's beneficial effect in patients with congestive heart failure. Initially, diuretics lower blood pressure by causing hypovolemia (decreased plasma and extracellular fluid), a temporary increase in glomerular filtration rate, and a decreased cardiac output. Cardiac output eventually returns to normal, but peripheral resistance is now reduced, resulting in lower blood pressure. In general, diuretics worsen glucose tolerance. In addition, loop diuretics have been associated with hypercholesterolemia and hypertriglyceridemia.

    PHARMACOKINETICS

    Furosemide is administered orally and intravenously.It is 95% plasma protein-bound, crosses the placenta, and appears in breast milk. Furosemide undergoes minimal metabolism in the liver, with 50—80% of a dose excreted in the urine within 24 hours. The remainder of the drug is eliminated through nonrenal mechanisms including excretion in the feces. In patients with significant renal impairment, nonrenal elimination can increase to 98%. The half-life of furosemide is approximately 0.5—1 hour.

    Oral Route

    Furosemide is absorbed erratically following an oral dose, and food will delay this absorption but will not alter the diuretic response. Diuresis generally begins 30 to 60 minutes after oral administration.

    Intravenous Route

    Diuresis generally begins about 5 minutes after IV administration of furosemide.