PDR MEMBER LOGIN:
  • PDR Search

    Required field
  • Advertisement
  • CLASSES

    Miscellaneous Agents for Obesity

    DEA CLASS

    Rx, schedule IV

    DESCRIPTION

    Serotonin 2C (5-HT2C) receptor agonist for weight loss
    Decreases food consumption and promotes satiety centrally; precise mechanism unknown
    Feb 2020, FDA requested voluntary withdrawal from market due to potential increased cancer risk

    COMMON BRAND NAMES

    Belviq, Belviq XR

    HOW SUPPLIED

    Belviq XR/Lorcaserin/Lorcaserin hydrochloride Oral Tab ER: 20mg
    Belviq/Lorcaserin/Lorcaserin hydrochloride Oral Tab: 10mg

    DOSAGE & INDICATIONS

    For the treatment of obesity† and for chronic weight management† as an adjunct to a reduced-calorie diet and increased physical activity.
    Oral dosage (immediate-release tablets; e.g., Belviq)
    Adults

    Not recommended. FDA requested voluntary withdrawal from the U.S. market due to an increased occurrence of cancer in treated patients.[64929] [64992] Previously recommended dosing: 10 mg PO twice daily. Evaluate response by week 12. If a patient has not lost at least 5% of baseline body weight, discontinue lorcaserin, as it is unlikely that the patient will achieve and sustain clinically meaningful weight loss with continued treatment.[51065]

    Oral dosage (extended-release tablets; e.g., Belviq XR)
    Adults

    Not recommended. FDA requested voluntary withdrawal from the U.S. market due to an increased occurrence of cancer in treated patients.[64929] [64992] Previously recommended dosing: 20 mg PO once daily. Evaluate response by week 12. If a patient has not lost at least 5% of baseline body weight, discontinue lorcaserin, as it is unlikely that the patient will achieve and sustain clinically meaningful weight loss with continued treatment.[61014]

    †Indicates off-label use

    MAXIMUM DOSAGE

    Adults

    20 mg/day PO.

    Geriatric

    20 mg/day PO.

    Adolescents

    Safety and efficacy have not been established.

    Children

    Safety and efficacy have not been established.

    Infants

    Safety and efficacy have not been established.

    Neonates

    Safety and efficacy have not been established.

    DOSING CONSIDERATIONS

    Hepatic Impairment

    Mild to moderate hepatic impairment (Child Pugh Class A or B): No dose adjustment required.
    Severe hepatic impairment (Child Pugh Class C): Not evaluated; use with caution.

    Renal Impairment

    CrCl more than 50 mL/min: No dose adjustment required.
    CrCl 30 to 50 mL/min: Use with caution in moderate renal impairment.
    CrCl less than 30 mL/min: Not recommended in severe renal impairment or end stage renal disease.
     
    Intermittent hemodialysis
    Not recommended.

    ADMINISTRATION

    Oral Administration
    Oral Solid Formulations

    Immediate-release tablets (i.e., Belviq): May be administered with or without food.
    Extended-release tablets (i.e., Belviq XR): May be administered with or without food. Swallow tablets whole; do not chew, crush, or divide.

    STORAGE

    Belviq:
    - Protect from extreme heat
    - Protect from moisture
    - Store at room temperature (between 59 to 86 degrees F)
    Belviq XR:
    - Avoid exposure to heat
    - Protect from light
    - Protect from moisture
    - Store at room temperature (between 59 to 86 degrees F)

    CONTRAINDICATIONS / PRECAUTIONS

    General Information

    Lorcaserin is contraindicated in patients with prior hypersensitivity to lorcaserin or to any of the product components. Hypersensitivity reactions have been reported.

    MAOI therapy

    Lorcaserin is a serotonergic drug. The development of potentially life-threatening serotonin syndrome or a Neuroleptic Malignant Syndrome (NMS)-like reaction has been reported during use of serotonergic drugs, particularly when such drugs are combined. Clinicians are advised to review potential drug interactions. The safety of lorcaserin when combined with monoamine oxidase inhibitor therapy (MAOI therapy), is not established and should be avoided, as MAOIs impair serotonin metabolism. The safety of the use of other serotonergic or antidopaminergic agents with lorcaserin, including antipsychotics, herbal or dietary supplements, or drugs that impair the metabolism of serotonin, has not been systematically evaluated and has not been established. If concomitant administration of lorcaserin with an agent that affects the serotonergic neurotransmitter system is clinically warranted, extreme caution and careful observation of the patient is advised, particularly during treatment initiation and dose increases.[51065] Serotonin syndrome symptoms may include mental status changes (e.g., agitation, hallucinations, coma), autonomic instability (e.g., tachycardia, labile blood pressure, hyperthermia), neuromuscular aberrations (e.g., hyperreflexia, incoordination) and gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). Serotonin syndrome, in its most severe form, can resemble neuroleptic malignant syndrome, which includes hyperthermia, muscle rigidity, autonomic instability with a possible rapid fluctuation of vital signs, and mental status changes. Patients should be monitored for the emergence of serotonin syndrome or NMS-like signs and symptoms. If these occur, discontinue lorcaserin and any other serotonergic or anti-dopaminergic agents immediately and institute supportive symptomatic treatment.[51065]

    Heart failure, valvular heart disease

    The effect of lorcaserin on cardiovascular morbidity and mortality has not been established. Regurgitant valvular heart disease, primarily affecting the mitral and/or aortic valves, has been reported in patients who took serotonergic drugs with 5-HT2B receptor agonist activity. The etiology of the regurgitant valvular disease is thought to be activation of 5-HT2B receptors on cardiac interstitial cells. At therapeutic concentrations, lorcaserin is selective for serotonin 5-HT2C receptors as compared to 5-HT2B receptors. In clinical trials, non-symptomatic valvular regurgitation was observed in lorcaserin treated patients. Lorcaserin has not been studied in patients with congestive heart failure or hemodynamically significant valvular heart disease. Preliminary data suggest that 5-HT2B receptors may be overexpressed in congestive heart failure. Therefore, lorcaserin should be used with caution in patients with congestive heart failure. Lorcaserin should not be used in combination with serotonergic and dopaminergic drugs that are potent 5-HT2B receptor agonists (e.g., cabergoline) and are known to increase the risk for cardiac valvulopathy. Patients who develop signs or symptoms of valvular heart disease, including dyspnea, dependent edema, congestive heart failure, or a new cardiac murmur while being treated with lorcaserin should be evaluated; consider discontinuation of lorcaserin. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, data are insufficient regarding the use of lorcaserin in obese patients with heart failure and use in this population should be avoided.

    AV block, bradycardia, bundle-branch block, sick sinus syndrome

    Use lorcaserin with caution in patients with bradycardia, sick sinus syndrome, bundle-branch block or a history of AV block (greater than first degree). In clinical trials, lorcaserin use was associated with mild reductions in heart rate vs. placebo. In clinical trials of at least 1-year in duration, the mean change in heart rate (HR) was -1.2 beats per minute (bpm) in locaserin-treated patients without diabetes and -2 bpm in treated patients with type 2 diabetes. The incidence of a HR less than 50 bpm was 5.3% in lorcaserin-treated patients without diabetes and 3.6% in treated patients with type 2 diabetes. Bradycardia occurred in 0.3% of lorcaserin-treated patients overall. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, lorcaserin is one of the preferred weight loss medications for obese patients with existing hypertension, established coronary artery disease, or cardiac arrhythmias. The drug has little effect on blood pressure and pulse compared to other prescribed weight management medications and has been consistentlyshown to improve CV risk factors in clinical trials as weight loss ensues. The effect of lorcaserin on cardiovascular morbidity and mortality has not been established; cardiovascular outcome trials are planned or ongoing.

    Driving or operating machinery

    In clinical trials of at least 1 year in duration, impairments in attention and memory were reported adverse reactions in 1.9% of patients treated with lorcaserin and at higher rates than with placebo. Other reported adverse reactions associated with lorcaserin in clinical trials included confusion, somnolence, and fatigue. Since lorcaserin has the potential to impair cognitive function, patients should be cautioned about driving or operating machinery or performing other potentially hazardous tasks, until they are aware of how this medication affects them.

    Depression, schizophrenia, suicidal ideation

    Use lorcaserin with particular caution in patients with a medical history of depression or psychiatric disorders with emotional lability. Do not exceed recommended doses. Events of euphoria, hallucination, and dissociation were seen with lorcaserin at supratherapeutic doses in short-term studies. In clinical trials of at least 1-year in duration, 0.2% of lorcaserin developed euphoria (rate higher than with placebo) at recommended doses. Some weight-loss drugs that target the central nervous system have been associated with depression or suicidal ideation. Patients treated with lorcaserin should be monitored for the emergence or worsening of depression, suicidal thoughts or behavior, and any unusual changes in mood or behavior. Discontinue use in patients who experience suicidal thoughts or behaviors.[51065] According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, there are insufficient safety data on the use of lorcaserin in obese patients with depression. Use with caution and avoid lorcaserin in patients taking medication for depression or in combination with other serotonergic agents. All patients undergoing weight loss therapy should be monitored for mood disorders, depression, and suicidal ideation. Evidence assessing safety and efficacy of weight loss medications in obese patients with a psychotic disorder (e.g., schizophrenia) is insufficient, and use of lorcaserin should be avoided. The AACE/ACE Obesity Guidelines recommend that patients receiving an antipsychotic be treated with structured lifestyle modifications to promote weight loss and weight gain prevention; metformin may be beneficial for modest weight loss and metabolic improvements in patients receiving an antipsychotic.[62881]

    Diabetes mellitus, hypoglycemia

    In clinical trials, lorcaserin use was associated with reports of hypoglycemia in patients with type 2 diabetes mellitus (T2DM). Blood glucose monitoring is warranted in patients with diabetes before and during lorcaserin treatment. In general, weight reduction may increase the risk of hypoglycemia in patients with T2DM treated with insulin and/or insulin secretagogues (e.g., sulfonylureas). Lorcaserin has not been systematically studied in combination with insulin. Dosage adjustments of anti-diabetic medications may be necessary. If a patient develops hypoglycemia during treatment, appropriate changes should be made to the antidiabetic drug regimen. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, weight loss medications should be considered as an adjunct to lifestyle therapy in all patients with type 2 diabetes as needed for weight loss sufficient to improve glycemic control, lipids, and blood pressure. There are insufficient data to determine if lorcaserin prevents progression to T2DM in obese patients. In controlled trials of other prescribed weight loss medications (i.e., orlistat, phentermine; topiramate, or liraglutide) as an adjunct to lifestyle therapy versus lifestyle therapy alone for diabetes prevention, a greater weight loss and more profound reductions in incident diabetes occurred in the medication plus lifestyle therapy groups.

    Leukemia, multiple myeloma, Peyronie's disease, priapism, sickle cell disease

    Priapism (painful erections greater than 6 hours in duration) is a potential effect of the serotonin receptor agonist effect of lorcaserin. If not treated promptly, priapism can result in irreversible damage to the erectile tissue. Men who have an erection lasting greater than 4 hours, whether painful or not, should immediately discontinue the drug and seek emergency medical attention. Use lorcaserin with caution in men who have conditions that might predispose them to priapism (e.g., sickle cell disease, multiple myeloma, or leukemia), or in men with anatomical deformation of the penis (e.g., angulation, cavernosal fibrosis, or Peyronie's disease). There is limited experience of the use of lorcaserin in men taking medications for erectile dysfunction.[51065]

    Anemia, leukopenia, neutropenia

    In clinical trials, adverse reactions of decreases in white blood cell count (including leukopenia, lymphopenia, neutropenia, and decreased white cell count) were reported in 0.4% of patients receiving lorcaserin and at rates higher than with placebo. Decreases in red blood cell count (including anemia or decreases in hemoglobin and hematocrit) were also reported at rates only slightly higher than placebo. Clinicians should consider periodic monitoring of complete blood count (CBC) during treatment with lorcaserin.

    Hyperprolactinemia

    Lorcaserin moderately elevates prolactin levels. Clinicians should measure prolactin levels when signs and symptoms of hyperprolactinemia are suspected (e.g., galactorrhea, gynecomastia, menstrual irregularity, infertility). In a subset of placebo-controlled clinical trials of at least 1 year in duration, elevations of prolactin more than the upper limit of normal (ULN), 2 times the ULN, and 5 times the ULN, measured both before and 2 hours after dosing, occurred in 6.7%, 1.7%, and 0.1% of lorcaserin-treated patients and at rates higher than with placebo. There was 1 patient treated with lorcaserin who developed a prolactinoma during clinical trials; the relationship of lorcaserin to the prolactinoma in this patient is unknown.[51065]

    Dialysis, renal disease, renal failure, renal impairment

    Lorcaserin use in patients with severe renal impairment or end-stage renal disease (renal failure) on dialysis is not recommended due to drug accumulation observed in pharmacokinetic studies. Administration of lorcaserin in patients with moderate renal impairment warrants caution; no dose adjustment is required in patients with mild renal impairment. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, lorcaserin can be used with appropriate caution in obese patients with mild to moderate renal impairment (i.e., CrCl 30 to 79 mL/minute). Accumulation of lorcaserin metabolites occurs in severe renal impairment (i.e., CrCl less than 30 mL/minute) and those with end-stage renal disease; the AACE/ACE Obesity Guidelines state to avoid use in these patients. Lorcaserin is a preferred weight loss medication in patients with a history of or at risk for nephrolithiasis, as the drug does not increase the risk for renal stones.

    Hepatic disease

    The effect of severe hepatic impairment on lorcaserin has not been not evaluated. Use lorcaserin with caution in patients with severe hepatic disease. Dose adjustment is not required for patients with mild to moderate hepatic impairment. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, all weight loss medications should be used cautiously in patients with hepatic impairment and should be avoided in severe liver impairment (i.e., Child-Pugh score greater than 9). Hepatic metabolism of lorcaserin may be affected in patients with mild to moderate hepatic impairment (i.e., Child-Pugh score of 5 to 9). While all obese patients have a potential risk for cholelithiasis and gallbladder disease, lorcaserin is not known to increase this risk.

    Alcoholism, anorexia nervosa, bariatric surgery, bulimia nervosa, substance abuse

    Locaserin use at higher than recommended doses may produce euphoria, hallucinations, and a potential for psychic dependence. It is likely not a preferred option for patients with a history of substance abuse, including alcoholism, without close monitoring for abuse. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, lorcaserin should be avoided in patients with alcoholism or other substance abuse due to the potential abuse potential. Other weight loss medications, including orlistat or liraglutide, should be considered in patients with a substance abuse disorder. Similar to other weight loss products, lorcaserin use by patients with selected eating disorders such as anorexia nervosa or bulimia nervosa may not be appropriate. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, there are insufficient data on the use of lorcaserin in overweight or obese patients with binge eating disorder (BED); however, there is a possible benefit on reduction in food cravings; administration of lorcaserin should occur along with non-medication interventions (i.e., behavioral/lifestyle program, psychotherapy). There are insufficient data regarding the benefits of lorcaserin following bariatric surgery.

    Pulmonary hypertension

    Certain centrally-acting weight loss agents that act on the serotonin system have been associated with pulmonary hypertension, a rare but lethal disease. Because of the low incidence of this disease, the clinical trial experience with lorcaserin is inadequate to determine if lorcaserin increases the risk for pulmonary hypertension.

    Geriatric

    Clinical studies of lorcaserin did not include sufficient numbers of geriatric subjects (65 years and older) to determine whether they respond differently from younger adults. Since older adult patients have a higher incidence of renal impairment, lorcaserin use in the geriatric adult should be made on the basis of renal function. Geriatric patients with normal renal function require no dose adjustment. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, there are insufficient data on the use of lorcaserin for weight reduction in elderly obese patients and additional studies are needed to assess safety and efficacy. Geriatric patients selected for weight loss therapy should have structured lifestyle interventions including reduced calorie meal plans and exercise, clear health-related goals including blood pressure reduction, diabetes prevention in high-risk patients with pre-diabetes, and improvements in osteoarthritis, mobility, and physical functioning. Overweight or obese elderly patients being considered for a weight loss medication should be evaluated for osteopenia and sarcopenia.

    Contraception requirements, labor, obstetric delivery, pregnancy

    Lorcaserin is contraindicated during pregnancy because weight loss offers no potential benefit to a pregnant woman and may result in fetal harm. Limited data on lorcaserin use in pregnant women are not sufficient to determine a drug-associated risk of major congenital malformations or miscarriage. No adverse developmental effects were observed when lorcaserin was administered to pregnant rats and rabbits during organogenesis at exposures up to 44- and 19-times the clinical dose of 20 mg/day, respectively. In rats, maternal exposure to lorcaserin in late pregnancy resulted in lower body weight in offspring which persisted to adulthood. If a female patient becomes pregnant while taking this drug, the patient should be apprised of the potential risk to the fetus.[51065] There is no accepted use of this drug during labor or obstetric delivery. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, weight loss medications must not be used during pregnancy and recommends that women be advised to adhere to contraception requirements. The AACE/ACE recommends women of childbearing potential receiving lorcaserin use adequate contraception during lorcaserin treatment and discontinue the drug if pregnancy occurs.[62881]

    Breast-feeding

    Because of the potential for serious adverse reactions in a breastfed infant, advise women that use of lorcaserin is not recommended while breast-feeding. There are no data on the presence of lorcaserin in human milk, the effects on the breastfed infant, or the effects on milk production. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, avoid the use of lorcaserin in lactating women who are breast-feeding.

    Children, infants

    The use of lorcaserin for the treatment of obesity is not recommended in children or adolescents. The safety and effectiveness of lorcaserin in pediatric patients below the age of 18 have not been established; do not give this drug to infants. In pediatric patients 12 years and older, pharmacotherapy is usually reserved for pediatric patients with a BMI at the 95th percentile or more or meeting the adult BMI recommendations for use. Reserve medication therapy for overweight children (BMI 85th to 94th percentile) in those with significant, severe comorbidities who have not responded to lifestyle modification. Only use medications with established benefit to risk ratios in this population.[58571] [63035]

    New primary malignancy

    Health care professionals should not prescribe or dispense lorcaserin due to a potentially increased risk of new primary malignancy. In February 2020, FDA requested that the manufacturer of Belviq, Belviq XR (lorcaserin) voluntarily withdraw the weight-loss drug from the U.S. market because a clinical safety trial showed an increased occurrence of cancer in treated patients. When lorcaserin was approved in 2012, FDA required the manufacturer to conduct a clinical trial to evaluate the risk of cardiovascular problems. Although the primary safety analysis showed no significant increase in cardiovascular risk, more patients in the lorcaserin group were diagnosed with cancer. A range of cancer types was reported in the trial, with pancreatic, colorectal, and lung cancer occurring more frequently in the lorcaserin group.

    ADVERSE REACTIONS

    Severe

    cardiac valvulopathy / Delayed / 0-2.4
    suicidal ideation / Delayed / 0.6-0.6
    bradycardia / Rapid / 0.3-0.3
    serotonin syndrome / Delayed / Incidence not known
    neuroleptic malignant syndrome-like symptoms / Delayed / Incidence not known
    visual impairment / Early / Incidence not known
    new primary malignancy / Delayed / Incidence not known

    Moderate

    hypoglycemia / Early / 0-29.3
    hyperprolactinemia / Delayed / 0.1-6.7
    blurred vision / Early / 0-6.3
    constipation / Delayed / 5.8-5.8
    hypertension / Early / 0-5.1
    peripheral edema / Delayed / 0-4.7
    impaired cognition / Early / 2.3-2.3
    depression / Delayed / 2.3-2.3
    lymphopenia / Delayed / 0-0.4
    leukopenia / Delayed / 0-0.4
    neutropenia / Delayed / 0-0.4
    confusion / Early / 0.2-0.2
    euphoria / Early / 0.2-0.2
    memory impairment / Delayed / Incidence not known
    conjunctivitis / Delayed / Incidence not known

    Mild

    headache / Early / 14.5-16.8
    infection / Delayed / 0-13.7
    back pain / Delayed / 0-11.7
    nausea / Early / 8.3-9.4
    dizziness / Early / 7.0-8.5
    cough / Delayed / 0-8.2
    fatigue / Early / 7.2-7.4
    diarrhea / Early / 6.5-6.5
    xerophthalmia / Early / 0-6.3
    xerostomia / Early / 5.3-5.3
    muscle cramps / Delayed / 0-4.7
    vomiting / Early / 3.8-3.8
    anxiety / Delayed / 3.5-3.5
    insomnia / Early / 3.5-3.5
    dental pain / Delayed / 2.7-2.7
    rash / Early / 0-2.1
    musculoskeletal pain / Early / 0-2.0
    chills / Rapid / 1.0-1.0
    tremor / Early / 0.3-0.3
    hyperhidrosis / Delayed / 0.1-0.1
    drowsiness / Early / Incidence not known

    DRUG INTERACTIONS

    Acarbose: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Acetaminophen; Caffeine; Dihydrocodeine: (Moderate) Concomitant use of dihydrocodeine with lorcaserin may increase dihydrocodeine plasma concentrations, but decrease the plasma concentration of the active metabolite, dihydromorphine, resulting in reduced efficacy or symptoms of opioid withdrawal. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage increase of dihydrocodeine until stable drug effects are achieved. Discontinuation of lorcaserin could decrease dihydrocodeine plasma concentrations and increase dihydromorphine plasma concentrations resulting in prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. If lorcaserin is discontinued, monitor the patient carefully and consider reducing the opioid dosage if appropriate. Dihydrocodeine is primarily metabolized by CYP2D6 to dihydromorphine, and by CYP3A4. Lorcaserin is a weak inhibitor of CYP2D6.
    Acetaminophen; Chlorpheniramine; Dextromethorphan: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Acetaminophen; Codeine: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Acetaminophen; Dextromethorphan: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Acetaminophen; Dextromethorphan; Doxylamine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Acetaminophen; Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Acetaminophen; Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Acetaminophen; Dextromethorphan; Phenylephrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Acetaminophen; Dextromethorphan; Pseudoephedrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Acetaminophen; Hydrocodone: (Moderate) Concomitant use of hydrocodone with lorcaserin may increase hydrocodone plasma concentrations and prolong opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when hydrocodone is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of hydrocodone until stable drug effects are achieved. Discontinuation of lorcaserin could decrease hydrocodone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to hydrocodone. If lorcaserin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Hydrocodone is a substrate for CYP2D6. Lorcaserin is an inhibitor of CYP2D6. Also, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Acetaminophen; Oxycodone: (Moderate) If concomitant use of oxycodone and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Acetohexamide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Albiglutide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Alfentanil: (Moderate) If concomitant use of alfentanil and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Alogliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Alogliptin; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Alogliptin; Pioglitazone: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Alpha-glucosidase Inhibitors: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Amitriptyline: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Amphetamines: (Moderate) Serotonin syndrome may occur during coadministration of serotonergic drugs such as amphetamines and lorcaserin. At high doses, amphetamines can increase serotonin release, as well as act as serotonin agonists. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly after a dose increase or the addition of other serotonergic medications to an existing regimen. Discontinue all serotonergic agents if serotonin syndrome occurs and implement appropriate medical management. Also, the safety and efficacy of coadministration of lorcaserin with other products for weight loss, including amphetamines, have not been established.
    Aspirin, ASA; Butalbital; Caffeine; Codeine: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Aspirin, ASA; Carisoprodol; Codeine: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Aspirin, ASA; Oxycodone: (Moderate) If concomitant use of oxycodone and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Atazanavir; Cobicistat: (Moderate) Caution is warranted when cobicistat is administered with lorcaserin as there is a potential for elevated cobicistat concentrations. Lorcaserin is a CYP2D6 inhibitor. Cobicistat is a substrate of CYP2D6.
    Atropine; Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate: (Major) Theoretically, concurrent use of methylene blue and lorcaserin may increase the risk of serotonin syndrome. Methylene blue is a thiazine dye that is also a potent, reversible inhibitor of the enzyme responsible for the catabolism of serotonin in the brain (MAO-A) and lorcaserin increases central serotonin effects). Cases of serotonin syndrome have been reported, primarily following administration of standard infusions of methylene blue (1 to 8 mg/kg) as a visualizing agent in parathyroid surgery, in patients receiving selective serotonin reuptake inhibitors, serotonin/norepinephrine reuptake inhibitors, or clomipramine. It is not known if patients receiving other serotonergic psychiatric agents with intravenous methylene blue are at a comparable risk or if methylene blue administered by other routes (e.g., orally, local injection) or in doses less than 1 mg/kg IV can produce a similar outcome. Published interaction reports between intravenously administered methylene blue and serotonergic psychiatric agents have documented symptoms including lethargy, confusion, delirium, agitation, aggression, obtundation, myoclonus, expressive aphasia, hypertonia, pyrexia, elevated blood pressure, seizures, and/or coma. Serotonin syndrome is characterized by rapid development of various symptoms such as hyperthermia, hypertension, myoclonus, rigidity, hyperhidrosis, incoordination, diarrhea, mental status changes (e.g., confusion, delirium, or coma), and in rare cases, death.
    Benzoic Acid; Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate: (Major) Theoretically, concurrent use of methylene blue and lorcaserin may increase the risk of serotonin syndrome. Methylene blue is a thiazine dye that is also a potent, reversible inhibitor of the enzyme responsible for the catabolism of serotonin in the brain (MAO-A) and lorcaserin increases central serotonin effects). Cases of serotonin syndrome have been reported, primarily following administration of standard infusions of methylene blue (1 to 8 mg/kg) as a visualizing agent in parathyroid surgery, in patients receiving selective serotonin reuptake inhibitors, serotonin/norepinephrine reuptake inhibitors, or clomipramine. It is not known if patients receiving other serotonergic psychiatric agents with intravenous methylene blue are at a comparable risk or if methylene blue administered by other routes (e.g., orally, local injection) or in doses less than 1 mg/kg IV can produce a similar outcome. Published interaction reports between intravenously administered methylene blue and serotonergic psychiatric agents have documented symptoms including lethargy, confusion, delirium, agitation, aggression, obtundation, myoclonus, expressive aphasia, hypertonia, pyrexia, elevated blood pressure, seizures, and/or coma. Serotonin syndrome is characterized by rapid development of various symptoms such as hyperthermia, hypertension, myoclonus, rigidity, hyperhidrosis, incoordination, diarrhea, mental status changes (e.g., confusion, delirium, or coma), and in rare cases, death.
    Brompheniramine; Dextromethorphan; Guaifenesin: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Brompheniramine; Dextromethorphan; Phenylephrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Brompheniramine; Pseudoephedrine; Dextromethorphan: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Buprenorphine: (Moderate) If concomitant use of buprenorphine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Buprenorphine; Naloxone: (Moderate) If concomitant use of buprenorphine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Bupropion: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, bupropion. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Bupropion; Naltrexone: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, bupropion. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Butalbital; Acetaminophen; Caffeine; Codeine: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Cabergoline: (Moderate) The prolactin-lowering effect of cabergoline may be diminished by medications that increase prolactin levels such as lorcaserin. Lorcaserin moderately elevates prolactin levels.
    Canagliflozin; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Carbinoxamine; Dextromethorphan; Pseudoephedrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Celecoxib; Tramadol: (Moderate) Monitor patients closely for adverse reactions including opioid withdrawal, seizures, and serotonin syndrome if coadministration with lorcaserin is necessary. If lorcaserin is discontinued, consider a tramadol dosage reduction until stable drug effects are achieved. Monitor patients closely for adverse events including respiratory depression and sedation. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. Concurrent use of lorcaserin, a CYP2D6 inhibitor, may increase tramadol exposure and decrease exposure to the active metabolite M1. Since M1 is a more potent mu-opioid agonist, decreased M1 exposure could result in decreased therapeutic effects. Increased tramadol exposure can result in increased or prolonged therapeutic effects and increased risk for serious adverse events.
    Chlordiazepoxide; Amitriptyline: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Chlorpheniramine; Codeine: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Chlorpheniramine; Dextromethorphan: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Chlorpheniramine; Dihydrocodeine; Phenylephrine: (Moderate) Concomitant use of dihydrocodeine with lorcaserin may increase dihydrocodeine plasma concentrations, but decrease the plasma concentration of the active metabolite, dihydromorphine, resulting in reduced efficacy or symptoms of opioid withdrawal. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage increase of dihydrocodeine until stable drug effects are achieved. Discontinuation of lorcaserin could decrease dihydrocodeine plasma concentrations and increase dihydromorphine plasma concentrations resulting in prolonged opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. If lorcaserin is discontinued, monitor the patient carefully and consider reducing the opioid dosage if appropriate. Dihydrocodeine is primarily metabolized by CYP2D6 to dihydromorphine, and by CYP3A4. Lorcaserin is a weak inhibitor of CYP2D6.
    Chlorpheniramine; Hydrocodone: (Moderate) Concomitant use of hydrocodone with lorcaserin may increase hydrocodone plasma concentrations and prolong opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when hydrocodone is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of hydrocodone until stable drug effects are achieved. Discontinuation of lorcaserin could decrease hydrocodone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to hydrocodone. If lorcaserin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Hydrocodone is a substrate for CYP2D6. Lorcaserin is an inhibitor of CYP2D6. Also, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Chlorpropamide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Citalopram: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, selective serotonin reuptake inhibitors (SSRIs). Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Clomipramine: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Cobicistat: (Moderate) Caution is warranted when cobicistat is administered with lorcaserin as there is a potential for elevated cobicistat concentrations. Lorcaserin is a CYP2D6 inhibitor. Cobicistat is a substrate of CYP2D6.
    Codeine: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Codeine; Guaifenesin: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Codeine; Guaifenesin; Pseudoephedrine: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Codeine; Phenylephrine; Promethazine: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Codeine; Promethazine: (Moderate) If concomitant use of codeine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Dapagliflozin; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Dapagliflozin; Saxagliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Darunavir; Cobicistat: (Moderate) Caution is warranted when cobicistat is administered with lorcaserin as there is a potential for elevated cobicistat concentrations. Lorcaserin is a CYP2D6 inhibitor. Cobicistat is a substrate of CYP2D6.
    Darunavir; Cobicistat; Emtricitabine; Tenofovir alafenamide: (Moderate) Caution is warranted when cobicistat is administered with lorcaserin as there is a potential for elevated cobicistat concentrations. Lorcaserin is a CYP2D6 inhibitor. Cobicistat is a substrate of CYP2D6.
    Degarelix: (Major) Avoid coadministration of degarelix with lorcaserin due to the risk of reduced efficacy of degarelix. Lorcaserin can cause hyperprolactinemia, which reduces the number of pituitary gonadotropin releasing hormone (GnRH) receptors; degarelix is a GnRH analog.
    Desipramine: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Dextromethorphan: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Dextromethorphan; Bupropion: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, bupropion. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms. (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Dextromethorphan; Diphenhydramine; Phenylephrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Dextromethorphan; Guaifenesin: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Dextromethorphan; Guaifenesin; Phenylephrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Dextromethorphan; Guaifenesin; Potassium Guaiacolsulfonate: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Dextromethorphan; Guaifenesin; Pseudoephedrine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Dextromethorphan; Quinidine: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Dipeptidyl Peptidase-4 Inhibitors: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Doxepin: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Doxorubicin Liposomal: (Major) Lorcaserin is a mild CYP2D6 inhibitor and doxorubicin is a major CYP2D6 substrate. Clinically significant interactions have been reported when doxorubicin was coadministered with inhibitors of CYP2D6, resulting in increased concentration and clinical effect of doxorubicin. Avoid coadministration of locaserin and doxorubicin if possible. If not possible, closely monitor for increased side effects of doxorubicin including myelosuppression and cardiotoxicity.
    Doxorubicin: (Major) Lorcaserin is a mild CYP2D6 inhibitor and doxorubicin is a major CYP2D6 substrate. Clinically significant interactions have been reported when doxorubicin was coadministered with inhibitors of CYP2D6, resulting in increased concentration and clinical effect of doxorubicin. Avoid coadministration of locaserin and doxorubicin if possible. If not possible, closely monitor for increased side effects of doxorubicin including myelosuppression and cardiotoxicity.
    Dulaglutide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Eliglustat: (Moderate) Monitor for an increase in the frequency and severity of eliglustat-related adverse effects if concomitant use with lorcaserin is necessary. Concomitant use may increase eliglustat exposure. Eliglustat is a CYP2D6 substrate and lorcaserin is a weak CYP2D6 inhibitor.
    Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Alafenamide: (Moderate) Caution is warranted when cobicistat is administered with lorcaserin as there is a potential for elevated cobicistat concentrations. Lorcaserin is a CYP2D6 inhibitor. Cobicistat is a substrate of CYP2D6.
    Elvitegravir; Cobicistat; Emtricitabine; Tenofovir Disoproxil Fumarate: (Moderate) Caution is warranted when cobicistat is administered with lorcaserin as there is a potential for elevated cobicistat concentrations. Lorcaserin is a CYP2D6 inhibitor. Cobicistat is a substrate of CYP2D6.
    Empagliflozin; Linagliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Empagliflozin; Linagliptin; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Empagliflozin; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Ertugliflozin; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Ertugliflozin; Sitagliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Escitalopram: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, selective serotonin reuptake inhibitors (SSRIs). Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Exenatide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Fenfluramine: (Moderate) Use fenfluramine and lorcaserin with caution due to an increased risk of serotonin syndrome. Monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs.
    Fentanyl: (Moderate) If concomitant use of fentanyl and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Fluoxetine: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, selective serotonin reuptake inhibitors (SSRIs). Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Fluvoxamine: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, selective serotonin reuptake inhibitors (SSRIs). Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Glimepiride: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Glimepiride; Rosiglitazone: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Glipizide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Glipizide; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Glyburide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Glyburide; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Goserelin: (Major) Avoid coadministration of goserelin with lorcaserin due to the risk of reduced efficacy of goserelin. Lorcaserin can cause hyperprolactinemia, which reduces the number of pituitary gonadotropin releasing hormone (GnRH) receptors; goserelin is a GnRH analog.
    Guaifenesin; Hydrocodone: (Moderate) Concomitant use of hydrocodone with lorcaserin may increase hydrocodone plasma concentrations and prolong opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when hydrocodone is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of hydrocodone until stable drug effects are achieved. Discontinuation of lorcaserin could decrease hydrocodone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to hydrocodone. If lorcaserin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Hydrocodone is a substrate for CYP2D6. Lorcaserin is an inhibitor of CYP2D6. Also, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Guaifenesin; Hydrocodone; Pseudoephedrine: (Moderate) Concomitant use of hydrocodone with lorcaserin may increase hydrocodone plasma concentrations and prolong opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when hydrocodone is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of hydrocodone until stable drug effects are achieved. Discontinuation of lorcaserin could decrease hydrocodone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to hydrocodone. If lorcaserin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Hydrocodone is a substrate for CYP2D6. Lorcaserin is an inhibitor of CYP2D6. Also, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Histrelin: (Major) Avoid coadministration of histrelin with lorcaserin due to the risk of reduced efficacy of histrelin. Lorcaserin can cause hyperprolactinemia, which reduces the number of pituitary gonadotropin releasing hormone (GnRH) receptors; histrelin is a GnRH analog.
    Homatropine; Hydrocodone: (Moderate) Concomitant use of hydrocodone with lorcaserin may increase hydrocodone plasma concentrations and prolong opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when hydrocodone is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of hydrocodone until stable drug effects are achieved. Discontinuation of lorcaserin could decrease hydrocodone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to hydrocodone. If lorcaserin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Hydrocodone is a substrate for CYP2D6. Lorcaserin is an inhibitor of CYP2D6. Also, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Hydrocodone: (Moderate) Concomitant use of hydrocodone with lorcaserin may increase hydrocodone plasma concentrations and prolong opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when hydrocodone is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of hydrocodone until stable drug effects are achieved. Discontinuation of lorcaserin could decrease hydrocodone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to hydrocodone. If lorcaserin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Hydrocodone is a substrate for CYP2D6. Lorcaserin is an inhibitor of CYP2D6. Also, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Hydrocodone; Ibuprofen: (Moderate) Concomitant use of hydrocodone with lorcaserin may increase hydrocodone plasma concentrations and prolong opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when hydrocodone is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of hydrocodone until stable drug effects are achieved. Discontinuation of lorcaserin could decrease hydrocodone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to hydrocodone. If lorcaserin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Hydrocodone is a substrate for CYP2D6. Lorcaserin is an inhibitor of CYP2D6. Also, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Hydrocodone; Pseudoephedrine: (Moderate) Concomitant use of hydrocodone with lorcaserin may increase hydrocodone plasma concentrations and prolong opioid adverse reactions, including hypotension, respiratory depression, profound sedation, coma, and death. It is recommended to avoid this combination when hydrocodone is being used for cough. If coadministration is necessary, monitor patients closely at frequent intervals and consider a dosage reduction of hydrocodone until stable drug effects are achieved. Discontinuation of lorcaserin could decrease hydrocodone plasma concentrations, decrease opioid efficacy, and potentially lead to a withdrawal syndrome in those with physical dependence to hydrocodone. If lorcaserin is discontinued, monitor the patient carefully and consider increasing the opioid dosage if appropriate. Hydrocodone is a substrate for CYP2D6. Lorcaserin is an inhibitor of CYP2D6. Also, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Hydromorphone: (Moderate) If concomitant use of hydromorphone and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Hyoscyamine; Methenamine; Methylene Blue; Phenyl Salicylate; Sodium Biphosphate: (Major) Theoretically, concurrent use of methylene blue and lorcaserin may increase the risk of serotonin syndrome. Methylene blue is a thiazine dye that is also a potent, reversible inhibitor of the enzyme responsible for the catabolism of serotonin in the brain (MAO-A) and lorcaserin increases central serotonin effects). Cases of serotonin syndrome have been reported, primarily following administration of standard infusions of methylene blue (1 to 8 mg/kg) as a visualizing agent in parathyroid surgery, in patients receiving selective serotonin reuptake inhibitors, serotonin/norepinephrine reuptake inhibitors, or clomipramine. It is not known if patients receiving other serotonergic psychiatric agents with intravenous methylene blue are at a comparable risk or if methylene blue administered by other routes (e.g., orally, local injection) or in doses less than 1 mg/kg IV can produce a similar outcome. Published interaction reports between intravenously administered methylene blue and serotonergic psychiatric agents have documented symptoms including lethargy, confusion, delirium, agitation, aggression, obtundation, myoclonus, expressive aphasia, hypertonia, pyrexia, elevated blood pressure, seizures, and/or coma. Serotonin syndrome is characterized by rapid development of various symptoms such as hyperthermia, hypertension, myoclonus, rigidity, hyperhidrosis, incoordination, diarrhea, mental status changes (e.g., confusion, delirium, or coma), and in rare cases, death.
    Ibuprofen; Oxycodone: (Moderate) If concomitant use of oxycodone and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Imipramine: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Incretin Mimetics: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Insulin Degludec; Liraglutide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Insulin Glargine; Lixisenatide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Insulins: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Lasmiditan: (Moderate) Serotonin syndrome may occur during coadministration of lasmiditan and lorcaserin. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome, particularly after a dose increase or the addition of other serotonergic medications to an existing regimen. Discontinue all serotonergic agents if serotonin syndrome occurs and implement appropriate medical management.
    Leuprolide: (Major) Avoid coadministration of leuprolide with lorcaserin due to the risk of reduced efficacy of leuprolide. Lorcaserin can cause hyperprolactinemia, which reduces the number of pituitary gonadotropin releasing hormone (GnRH) receptors; leuprolide is a GnRH analog.
    Leuprolide; Norethindrone: (Major) Avoid coadministration of leuprolide with lorcaserin due to the risk of reduced efficacy of leuprolide. Lorcaserin can cause hyperprolactinemia, which reduces the number of pituitary gonadotropin releasing hormone (GnRH) receptors; leuprolide is a GnRH analog.
    Levorphanol: (Moderate) If concomitant use of levorphanol and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Linagliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Linagliptin; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Linezolid: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including linezolid, an antibiotic that is also a reversible, non-selective MAO inhibitor. Serious CNS reactions, such as serotonin syndrome, have been reported during the concurrent clinical use of linezolid and medications that enhance central serotonergic activity.
    Liraglutide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Lithium: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, lithium. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Lixisenatide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Meglitinides: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Meperidine: (Moderate) If concomitant use of meperidine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Meperidine; Promethazine: (Moderate) If concomitant use of meperidine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Metformin; Repaglinide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Metformin; Rosiglitazone: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Metformin; Saxagliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Metformin; Sitagliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Methadone: (Moderate) Monitor patients for respiratory depression and sedation at frequent intervals if concomitant administration of methadone and lorcaserin is necessary; consider reducing the methadone dose until stable effects are achieved. Concomitant use of methadone and lorcaserin may increase the plasma concentration of methadone, resulting in increased or prolonged opioid effects. If lorcaserin is discontinued, consider increasing the methadone dose until stable drug effects are achieved and monitor for evidence of opioid withdrawal. Methadone is a CYP2D6 substrate and lorcaserin is a CYP2D6 inhibitor. Also monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Methenamine; Sodium Acid Phosphate; Methylene Blue; Hyoscyamine: (Major) Theoretically, concurrent use of methylene blue and lorcaserin may increase the risk of serotonin syndrome. Methylene blue is a thiazine dye that is also a potent, reversible inhibitor of the enzyme responsible for the catabolism of serotonin in the brain (MAO-A) and lorcaserin increases central serotonin effects). Cases of serotonin syndrome have been reported, primarily following administration of standard infusions of methylene blue (1 to 8 mg/kg) as a visualizing agent in parathyroid surgery, in patients receiving selective serotonin reuptake inhibitors, serotonin/norepinephrine reuptake inhibitors, or clomipramine. It is not known if patients receiving other serotonergic psychiatric agents with intravenous methylene blue are at a comparable risk or if methylene blue administered by other routes (e.g., orally, local injection) or in doses less than 1 mg/kg IV can produce a similar outcome. Published interaction reports between intravenously administered methylene blue and serotonergic psychiatric agents have documented symptoms including lethargy, confusion, delirium, agitation, aggression, obtundation, myoclonus, expressive aphasia, hypertonia, pyrexia, elevated blood pressure, seizures, and/or coma. Serotonin syndrome is characterized by rapid development of various symptoms such as hyperthermia, hypertension, myoclonus, rigidity, hyperhidrosis, incoordination, diarrhea, mental status changes (e.g., confusion, delirium, or coma), and in rare cases, death.
    Methylene Blue: (Major) Theoretically, concurrent use of methylene blue and lorcaserin may increase the risk of serotonin syndrome. Methylene blue is a thiazine dye that is also a potent, reversible inhibitor of the enzyme responsible for the catabolism of serotonin in the brain (MAO-A) and lorcaserin increases central serotonin effects). Cases of serotonin syndrome have been reported, primarily following administration of standard infusions of methylene blue (1 to 8 mg/kg) as a visualizing agent in parathyroid surgery, in patients receiving selective serotonin reuptake inhibitors, serotonin/norepinephrine reuptake inhibitors, or clomipramine. It is not known if patients receiving other serotonergic psychiatric agents with intravenous methylene blue are at a comparable risk or if methylene blue administered by other routes (e.g., orally, local injection) or in doses less than 1 mg/kg IV can produce a similar outcome. Published interaction reports between intravenously administered methylene blue and serotonergic psychiatric agents have documented symptoms including lethargy, confusion, delirium, agitation, aggression, obtundation, myoclonus, expressive aphasia, hypertonia, pyrexia, elevated blood pressure, seizures, and/or coma. Serotonin syndrome is characterized by rapid development of various symptoms such as hyperthermia, hypertension, myoclonus, rigidity, hyperhidrosis, incoordination, diarrhea, mental status changes (e.g., confusion, delirium, or coma), and in rare cases, death.
    Miglitol: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Monoamine oxidase inhibitors: (Major) Avoid concurrent use of monoamine oxidase inhibitors (MAOIs) and lorcaserin if possible; use with extreme caution and only if medically necessary. MAOIs are not recommended to be taken with serotonergic medications due to the risk for serotonin syndrome. Lorcaserin affects serotonergic neurotransmitter systems. Patients receiving this combination should be monitored for the emergence of serotonin syndrome.
    Morphine: (Moderate) If concomitant use of morphine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Morphine; Naltrexone: (Moderate) If concomitant use of morphine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Nalbuphine: (Moderate) If concomitant use of nalbuphine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Nateglinide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Nebivolol: (Moderate) Monitor for increased toxicity as well as increased therapeutic effect of nebivolol if coadministered with lorcaserin. Nebivolol is metabolized by CYP2D6. Although data are lacking, CYP2D6 inhibitors, such as lorcaserin, could potentially increase nebivolol plasma concentrations via CYP2D6 inhibition; the clinical significance of this potential interaction is unknown, but an increase in adverse effects is possible.
    Nebivolol; Valsartan: (Moderate) Monitor for increased toxicity as well as increased therapeutic effect of nebivolol if coadministered with lorcaserin. Nebivolol is metabolized by CYP2D6. Although data are lacking, CYP2D6 inhibitors, such as lorcaserin, could potentially increase nebivolol plasma concentrations via CYP2D6 inhibition; the clinical significance of this potential interaction is unknown, but an increase in adverse effects is possible.
    Nortriptyline: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Olanzapine; Fluoxetine: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, selective serotonin reuptake inhibitors (SSRIs). Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Oliceridine: (Moderate) If concomitant use of oliceridine and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Orlistat: (Moderate) The safety and efficacy of coadministration of lorcaserin with other products intended for weight loss including prescription drugs (e.g., phentermine, fenfluramine, dexfenfluramine, orlistat, phendimetrazine, amphetamines), over-the-counter drugs (e.g., orlistat, phenylpropanolamine, ephedrine), and herbal preparations (ephedra, Ma huang) have not been established. Some of these agents (fenfluramine, dexfenfluramine) are known to increase the risk for cardiac valvulopathy and pulmonary hypertension. Co-use of sibutramine with other serotonergic medications is contraindicated due to the risk for serotonin-related adverse effects, such as serotonin syndrome.
    Oxycodone: (Moderate) If concomitant use of oxycodone and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Oxymorphone: (Moderate) If concomitant use of oxymorphone and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Ozanimod: (Major) Coadministration of ozanimod with lorcaserin is not recommended due to the potential for hypertensive crisis. If coadministration is necessary, closely monitor patients for hypertension. An active metabolite of ozanimod inhibits MAO-B, which may increase the potential for hypertensive crisis. Lorcaserin may increase blood pressure by increasing serotonin concentrations.
    Paroxetine: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, selective serotonin reuptake inhibitors (SSRIs). Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Perphenazine; Amitriptyline: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Phendimetrazine: (Major) The safety and efficacy of coadministration of lorcaserin with other products intended for weight loss including prescription drugs (e.g., phentermine, fenfluramine, dexfenfluramine, orlistat, phendimetrazine, amphetamines), over-the-counter drugs (e.g., orlistat, phenylpropanolamine, ephedrine), and herbal preparations (ephedra, Ma huang) have not been established. Some of these agents (fenfluramine, dexfenfluramine) are known to increase the risk for cardiac valvulopathy and pulmonary hypertension. Co-use of sibutramine with other serotonergic medications is contraindicated due to the risk for serotonin-related adverse effects, such as serotonin syndrome.
    Phentermine: (Major) The safety and efficacy of coadministration of lorcaserin with other products intended for weight loss including prescription drugs (e.g., phentermine, fenfluramine, dexfenfluramine, orlistat, phendimetrazine, amphetamines), over-the-counter drugs (e.g., orlistat, phenylpropanolamine, ephedrine), and herbal preparations (ephedra, Ma huang) have not been established. Some of these agents (fenfluramine, dexfenfluramine) are known to increase the risk for cardiac valvulopathy and pulmonary hypertension. Coadministration of sibutramine with other serotonergic medications is contraindicated due to the risk for serotonin-related adverse effects, such as serotonin syndrome.
    Phentermine; Topiramate: (Major) The safety and efficacy of coadministration of lorcaserin with other products intended for weight loss including prescription drugs (e.g., phentermine, fenfluramine, dexfenfluramine, orlistat, phendimetrazine, amphetamines), over-the-counter drugs (e.g., orlistat, phenylpropanolamine, ephedrine), and herbal preparations (ephedra, Ma huang) have not been established. Some of these agents (fenfluramine, dexfenfluramine) are known to increase the risk for cardiac valvulopathy and pulmonary hypertension. Coadministration of sibutramine with other serotonergic medications is contraindicated due to the risk for serotonin-related adverse effects, such as serotonin syndrome.
    Phosphodiesterase inhibitors: (Moderate) Lorcaserin is a serotonin 2C receptor agonist, and priapism is a potential effect of 5-HT2C receptor agonism. Because there is little experience with the combination of lorcaserin and medications indicated for erectile dysfunction (e.g., phosphodiesterase inhibitors), combined use should be approached with caution.
    Pioglitazone: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Pioglitazone; Glimepiride: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Pioglitazone; Metformin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Pramlintide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Promethazine; Dextromethorphan: (Moderate) Because of the potential risk and severity of serotonin syndrome, caution should be observed when administering dextromethorphan with lorcaserin. Both medications have serotonergic activity. Inform patients taking this combination of the possible increased risk and monitor for the emergence of serotonin syndrome particularly during treatment initiation and dose adjustment. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. In addition, lorcaserin inhibits CYP2D6-mediated metabolism of dextromethorphan, increasing dextromethorphan Cmax by approximately 76% and AUC by approximately 2-fold. Increased dextromethorphan exposure may result in adverse effects consistent with the serotonin syndrome.
    Protriptyline: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Remifentanil: (Moderate) If concomitant use of remifentanil and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Repaglinide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Rosiglitazone: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Saxagliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Selective serotonin reuptake inhibitors: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, selective serotonin reuptake inhibitors (SSRIs). Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Selegiline: (Moderate) Concomitant use of selegiline and lorcaserin may increase the risk of serotonin syndrome. Monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs.
    Semaglutide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Serotonin norepinephrine reuptake inhibitors: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, serotonin norepinephrine reuptake inhibitors. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Serotonin-Receptor Agonists: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, serotonin-receptor agonists. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Sertraline: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, selective serotonin reuptake inhibitors (SSRIs). Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Sibutramine: (Contraindicated) Co-use of sibutramine with other serotonergic medications is contraindicated due to the risk for serotonin-related adverse effects, such as serotonin syndrome. Serotonin syndrome is characterized by rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death. Serotonin syndrome, in its most severe form, can resemble neuroleptic malignant syndrome. The safety and efficacy of coadministration of lorcaserin with other products intended for weight loss have not been established.
    Simvastatin; Sitagliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Sitagliptin: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    St. John's Wort, Hypericum perforatum: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, St. John's Wort. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Sufentanil: (Moderate) If concomitant use of sufentanil and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Sulfonylureas: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Tapentadol: (Moderate) If concomitant use of tapentadol and lorcaserin is warranted, monitor patients for the emergence of serotonin syndrome. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.
    Thiazolidinediones: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Tirzepatide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Tolazamide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Tolbutamide: (Moderate) In general, weight reduction may increase the risk of hypoglycemia in patients with type 2 diabetes mellitus treated with antidiabetic agents, such as insulin and/or insulin secretagogues (e.g., sulfonylureas). In clinical trials, lorcaserin use was associated with reports of hypoglycemia. Blood glucose monitoring is warranted in patients with type 2 diabetes prior to starting and during lorcaserin treatment. Dosage adjustments of anti-diabetic medications should be considered. If a patient develops hypoglycemia during treatment, adjust anti-diabetic drug regimen accordingly. Of note, lorcaserin has not been studied in combination with insulin.
    Tramadol: (Moderate) Monitor patients closely for adverse reactions including opioid withdrawal, seizures, and serotonin syndrome if coadministration with lorcaserin is necessary. If lorcaserin is discontinued, consider a tramadol dosage reduction until stable drug effects are achieved. Monitor patients closely for adverse events including respiratory depression and sedation. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. Concurrent use of lorcaserin, a CYP2D6 inhibitor, may increase tramadol exposure and decrease exposure to the active metabolite M1. Since M1 is a more potent mu-opioid agonist, decreased M1 exposure could result in decreased therapeutic effects. Increased tramadol exposure can result in increased or prolonged therapeutic effects and increased risk for serious adverse events.
    Tramadol; Acetaminophen: (Moderate) Monitor patients closely for adverse reactions including opioid withdrawal, seizures, and serotonin syndrome if coadministration with lorcaserin is necessary. If lorcaserin is discontinued, consider a tramadol dosage reduction until stable drug effects are achieved. Monitor patients closely for adverse events including respiratory depression and sedation. Discontinue all serotonergic agents and initiate symptomatic treatment if serotonin syndrome occurs. Concurrent use of lorcaserin, a CYP2D6 inhibitor, may increase tramadol exposure and decrease exposure to the active metabolite M1. Since M1 is a more potent mu-opioid agonist, decreased M1 exposure could result in decreased therapeutic effects. Increased tramadol exposure can result in increased or prolonged therapeutic effects and increased risk for serious adverse events.
    Tricyclic antidepressants: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Trimipramine: (Moderate) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tricyclic antidepressants. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.
    Triptorelin: (Major) Avoid coadministration of triptorelin with lorcaserin due to the risk of reduced efficacy of triptorelin. Lorcaserin can cause hyperprolactinemia, which reduces the number of pituitary GnRH receptors; triptorelin is a GnRH analog.
    Tryptophan, 5-Hydroxytryptophan: (Major) Based on the mechanism of action of lorcaserin and the theoretical potential for serotonin syndrome, use with extreme caution in combination with other drugs that may affect the serotonergic neurotransmitter systems, including, tryptophan. Patients receiving this combination should be monitored for the emergence of serotonin syndrome or Neuroleptic Malignant Syndrome (NMS) like signs and symptoms.

    PREGNANCY AND LACTATION

    Pregnancy

    Lorcaserin is contraindicated during pregnancy because weight loss offers no potential benefit to a pregnant woman and may result in fetal harm. Limited data on lorcaserin use in pregnant women are not sufficient to determine a drug-associated risk of major congenital malformations or miscarriage. No adverse developmental effects were observed when lorcaserin was administered to pregnant rats and rabbits during organogenesis at exposures up to 44- and 19-times the clinical dose of 20 mg/day, respectively. In rats, maternal exposure to lorcaserin in late pregnancy resulted in lower body weight in offspring which persisted to adulthood. If a female patient becomes pregnant while taking this drug, the patient should be apprised of the potential risk to the fetus.[51065] There is no accepted use of this drug during labor or obstetric delivery. According to the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) Obesity Clinical Practice Guidelines, weight loss medications must not be used during pregnancy and recommends that women be advised to adhere to contraception requirements. The AACE/ACE recommends women of childbearing potential receiving lorcaserin use adequate contraception during lorcaserin treatment and discontinue the drug if pregnancy occurs.[62881]

    MECHANISM OF ACTION

    Lorcaserin is believed to decrease food consumption and promote satiety by selectively activating 5-HT2C receptors on anorexigenic pro-opiomelanocortin neurons located in the hypothalamus. The exact mechanism of action is not known. Lorcaserin at the recommended daily dose selectivity interacts with 5-HT2C receptors as compared to 5-HT2A and 5-HT2B receptors, other 5-HT receptor subtypes, the 5-HT receptor transporter, and 5-HT reuptake sites.

    PHARMACOKINETICS

    Lorcaserin is administered orally. Following administration, it distributes to the cerebrospinal fluid and central nervous system. It is approximately 70% bound to human plasma proteins. Metabolism occurs predominantly in the liver via multiple enzymatic pathways. Lorcaserin sulfamate (M1) represents a major circulating metabolite with a plasma Cmax that exceeds lorcaserin Cmax by 1- to 5-fold. The principal metabolites exert no pharmacological activity at serotonin receptors. The plasma half-life of immediate-release lorcaserin is approximately 11 hours and the half-life of extended-release lorcaserin is 12 hours. Parent drug and metabolites are excreted in the urine. In studies, 94.5% of radiolabeled material was recovered, with 92.3% and 2.2% recovered from urine and feces, respectively. The N-carbamoyl glucuronide lorcaserin (M5) is the major metabolite in urine; M1 is a minor metabolite in urine, representing approximately 3% of dose. Other minor metabolites excreted in urine were identified as glucuronide or sulfate conjugates of oxidative metabolites.
     
    Affected cytochrome P450 (CYP450) isoenzymes and drug transporters: CYP2D6
    Lorcaserin is extensively metabolized in the liver by multiple enzymatic pathways. Lorcaserin can decrease the metabolism of CYP2D6 substrates.. In one small trial of CYP2D6 extensive metabolizers, lorcaserin increased dextromethorphan peak concentrations by approximately 76% and AUC by about 2-fold.

    Oral Route

    The absolute bioavailability of lorcaserin has not been determined. Immediate-release lorcaserin reaches steady-state within 3 days after twice daily dosing, and accumulation is estimated to be about 70%. Following oral administration under steady-state conditions, peak plasma concentrations of immediate-release lorcaserin occur at 1.5hours compared to 10 hours for extended-release lorcaserin. Single dose administration of extended-release lorcaserin 20 mg results in a comparable total plasma exposure to 2 doses of immediate-release lorcaserin 10 mg administered 12 hours apart, and an approximate 25% lower peak exposure relative to the immediate-release tablets. However, at steady state, the Cmax and AUC of both formulations is bioequivalent under fasted conditions. Administration of immediate-release lorcaserin under fed conditions increased Cmax by approximately 9% and exposure (AUC) by approximately 5%; Tmax was delayed approximately 1 hour. Intake of high fat, high calorie breakfast before a single 20 mg oral dose of the extended-release formulation resulted in approximately 46% increase in Cmax and 17% increase in AUC but no change in Tmax. At steady state, however, there was no significant food effect on the rate or extent of absorption. Therefore, both immediate-release and extended-release lorcaserin may be administered without regard to meals.