Lorcaserin is a serotonergic drug. The development of a potentially life-threatening serotonin syndrome or neuroleptic malignant syndrome-like symptoms have been reported during use of serotonergic drugs. In clinical evaluation of immediate-release lorcaserin, 2 patients experienced signs and symptoms consistent with serotonergic excess, including 1 patient on concomitant dextromethorphan who reported an event of serotonin syndrome. Symptoms of possible serotonergic etiology that are included in the criteria for serotonin syndrome were reported by patients treated with lorcaserin and placebo during clinical trials of at least 1 year in duration. In both groups, chills were the most frequent of these events (1% vs. 0.2%, respectively), followed by tremor (0.3% vs. 0.2%), confusion (0.2% vs. less than 0.1%), disorientation (0.1% vs. 0.1%) and hyperhidrosis (0.1% vs. 0.2%). Serotonin-receptor agonist (triptan) and dextromethorphan use was permitted during evaluation; the safety of lorcaserin when combined with other serotonergic or antidopaminergic agents was not evaluated. Further, due to the low incidence of serotonin syndrome in clinical trials, an association between lorcaserin treatment and serotonin syndrome cannot be excluded.[51065] [61014]

Because cardiac valvulopathy as been reported in patients who took drugs with 5-HT2B receptor agonist activity, the possible occurrence of regurgitant cardiac valve disease was prospectively evaluated in 7794 patients in 3 clinical trials of at least 1 year in duration, 3451 of whom took immediate-release lorcaserin 10 mg twice daily. The primary echocardiographic safety parameter was the proportion of patients who developed echocardiographic criteria of mild or greater aortic insufficiency and/or moderate or greater mitral insufficiency from baseline to 1 year. At 1 year, 2.4% of patients who received lorcaserin and 2% of patients who received placebo developed valvular regurgitation. The pooled relative risk of FDA-defined valvulopathy associated with lorcaserin treatment was 1.16 among the 3 clinical trials. Lorcaserin was not studied in patients with congestive heart failure or hemodynamically-significant valvular heart disease.[51065] [61014]

Clinical evaluation of immediate-release lorcaserin included both non-diabetic and diabetic patients exposed to treatment for at least 1 year; a total of 1969 patients were exposed to lorcaserin 10 mg twice daily for 1 year and 426 patients were exposed for 2 years. Headache and dizziness were among the most common adverse reactions reported for non-diabetic patients treated with lorcaserin compared to placebo: headache (16.8% vs. 10.1%) and dizziness (8.5% vs. 3.8%). Adverse reactions reported by diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: headache (14.5% vs. 7.1%) and dizziness (7.0% vs. 6.3%). Overall, headache and dizziness were among common causes of treatment discontinuation. Other nervous system related adverse events reported in trials include: impaired cognition (e.g., difficulty with concentration/attention), memory impairment, drowsiness, and confusion) occurring in 2.3% of patients taking lorcaserin and 0.7% of patients taking placebo.[51065] [61014]

Clinical evaluation of immediate-release lorcaserin included both non-diabetic and diabetic patients exposed to treatment for at least 1 year; a total of 1969 patients were exposed to lorcaserin 10 mg twice daily for 1 year and 426 patients were exposed for 2 years. Depression was included within common adverse reactions leading to discontinuation more often among lorcaserin-treated patients than placebo. Psychiatric adverse reactions reported by 2% or more of diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: anxiety (3.5% vs. 3.2%), insomnia (3.5% vs. 2.4%), stress (2.7% vs. 1.2%), and depression (2.3% vs. 2%). In trials, suicidal ideation occurred in 0.6% lorcaserin-treated vs. 0.4% placebo-treated patients. In addition, euphoria was observed in 0.17% of patients taking lorcaserin and 0.03% taking placebo.[51065] [61014] Patients should promptly report depression or other unusual changes in mood or behaviors for evaluation.

Clinical evaluation of immediate-release lorcaserin included both non-diabetic and diabetic patients exposed to treatment for at least 1 year; a total of 1969 patients were exposed to lorcaserin 10 mg twice daily for 1 year and 426 patients were exposed for 2 years. Hypoglycemia was reported among the most common adverse events in diabetic patients, but the incidence in non-diabetic patients is not increased over placebo. Adverse reactions reported by 2% or more of diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: hypoglycemia (29.3% vs. 21%), worsening of diabetes mellitus (2.7% vs. 0.8%), and decreased appetite (2.3% vs. 0.4%). In a clinical trial of patients with type 2 diabetes mellitus, hypoglycemia requiring the assistance of another person occurred in 4 (1.6%) of lorcaserin-treated patients and in 1 (0.4%) placebo-treated patient. Of these 4 lorcaserin-treated patients, all were concomitantly using a sulfonylurea (with or without metformin). Lorcaserin has not been studied in patients taking insulin. Hypoglycemia defined as blood sugar 65 mg/dL or less and with symptoms occurred in 19 (7.4%) lorcaserin-treated patients and 16 (6.3%) placebo-treated patients.[51065] [61014]

Clinical evaluation of immediate-release lorcaserin included both non-diabetic and diabetic patients exposed to treatment for at least 1 year; a total of 1969 patients were exposed to lorcaserin 10 mg twice daily for 1 year and 426 patients were exposed for 2 years. Cardiovascular adverse reactions reported by 2% or more of diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: hypertension (5.1% vs. 3.2%). In addition, lorcaserin use was associated with a small incidence of mild bradycardia. In the combined population, adverse reactions of bradycardia occurred in 0.3% of lorcaserin and 0.1% of placebo-treated patients.[51065] [61014]

Clinical evaluation of immediate-release lorcaserin included both non-diabetic and diabetic patients exposed to treatment for at least 1 year; a total of 1969 patients were exposed to lorcaserin 10 mg twice daily for 1 year and 426 patients were exposed for 2 years. 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 (compared to 0.2% receiving placebo). In addition, lymphocyte counts were below the lower limit of normal in 12.2% of patients taking lorcaserin and 9% taking placebo, and neutrophil counts were low in 5.6% and 4.3%, respectively; 10.4% of patients taking lorcaserin and 9.3% taking placebo had hemoglobin below the lower limit of normal at some point during the trials. Immune related adverse reactions reported by 2% or more of non-diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: upper respiratory tract infection (13.7% vs. 12.3%), nasopharyngitis (13% vs. 12%), and urinary tract infection (6.5% vs. 5.4%). Events reported by diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: nasopharyngitis (11.3% vs. 9.9%) and urinary tract infection (9% vs. 6%).[51065] [61014]

Lorcaserin moderately elevates prolactin levels which can lead to hyperprolactinemia. In clinical trials of immediate-release lorcaserin, elevations of prolactin greater than the upper limit of normal (ULN), 2-times the ULN, and 5-times the ULN, occurred in 6.7%, 1.7%, and 0.1% of lorcaserin-treated patients and 4.8%, 0.8%, and 0% of placebo-treated patients, respectively.[51065] [61014]

Clinical evaluation of immediate-release lorcaserin included both non-diabetic and diabetic patients exposed to treatment for at least 1 year; a total of 1969 patients were exposed to lorcaserin 10 mg twice daily for 1 year and 426 patients were exposed for 2 years. For non-diabetic patients nausea, dry mouth, and constipation were reported among the most common adverse events. Gastrointestinal adverse reactions reported by 2% or more of non-diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: nausea (8.3% vs. 5.3%), diarrhea (6.5% vs. 5.6%), constipation (5.8% vs. 3.9%), xerostomia (5.3% vs. 2.3%), and vomiting (3.8% vs. 2.6%). Events reported by diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: nausea (9.4% vs. 7.9%), dental pain (2.7% vs. 0%), and gastroenteritis (3.1% vs. 2%).[51065] [61014]

A greater number of patients on immediate-release lorcaserin reported an eye disorder than patients on placebo in clinical trials of patients without diabetes (4.5% vs. 3%) and with type 2 diabetes (6.3% vs. 1.6%). In the population without diabetes, events of blurred vision, xerophthalmia, and visual impairment occurred in lorcaserin-treated patients at an incidence greater than that of placebo. In the population with type 2 diabetes, visual disorders, conjunctivitis, irritations, and inflammations, ocular sensation disorders, and cataract conditions occurred in lorcaserin-treated patients at an incidence greater than placebo.[51065] [61014]

Clinical evaluation of immediate-release lorcaserin included both non-diabetic and diabetic patients exposed to treatment for at least 1 year; a total of 1969 patients were exposed to lorcaserin 10 mg twice daily for 1 year and 426 patients were exposed for 2 years. For both non-diabetic and diabetic patients fatigue was reported among the most common adverse events. For diabetic patients the list also included back pain and cough. Adverse reactions reported by 2% or more of non-diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: fatigue (7.2% vs. 3.6%), back pain (6.3% vs. 5.6%), musculoskeletal pain (2% vs. 1.4%), cough (4.3% vs. 3.4%), oropharyngeal pain (3.5% vs. 2.5%), sinus congestion (2.9% vs. 2.4%), and rash (unspecified) (2.1% vs. 1.8%). Events reported by diabetic patients and more frequently reported by patients taking lorcaserin compared to placebo include: fatigue (7.4% vs. 4%), peripheral edema (4.7% vs. 2.4%), seasonal allergy (3.1% vs. 0.8%), back pain (11.7% vs. 7.9%), muscle cramps (4.7% vs. 3.6%), and cough (8.2% vs. 4.4%).[51065] [61014]

Lorcaserin may be associated with the development of a new primary malignancy. During a clinical trial (n = 12,000 patients) assessing the risk of heart-related problems, more patients receiving lorcaserin therapy were diagnosed with cancer during the 5-year trial period compared to patients taking placebo. Although a possible increased risk of cancer was reported, as of January 2020, a causal relationship to lorcaserin had not been established.[64929] In February 2020, after further analysis of the data, FDA requested that the manufacturer of Belviq, Belviq XR (lorcaserin) voluntarily withdraw the weight-loss drug from the U.S. market because the clinical safety trial showed this increased occurrence of cancer in treated patients. When lorcaserin was approved in 2012, FDA required the drug manufacturer to conduct a clinical trial to evaluate the risk of cardiovascular problems. A range of cancer types was reported in this study, with several different types of cancers occurring more frequently in the lorcaserin group, including pancreatic, colorectal, and lung cancer.[64992]

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]

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.[51065] 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.[62881]

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.[51065] 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 consistently
shown 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.[62881]

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.[51065]

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]

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.[51065] 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.[62881]

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]

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.[51065]

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]

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.[51065] 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.[62881]

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.[51065] 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.[62881]

Locaserin use at higher than recommended doses may produce euphoria, hallucinations, and a potential for psychic dependence.[51065] 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.[62881] 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).[62881] There are insufficient data regarding the benefits of lorcaserin following bariatric surgery.[62881]

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.[51065]

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.[51065] 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.[62881]

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]

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.[51065] 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.[62881]

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.[51065] 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]

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.[64992]