The injectable glucagon-like peptide-1 (GLP-1) receptor agonist semaglutide (Wegovy), which was approved by the FDA in 2021 for chronic weight management in adults, has now been approved for chronic weight management in children ≥12 years old with an initial BMI in the ≥95th percentile for age and sex.Semaglutide is also available as Ozempic and Rybelsus for treatment of type 2 diabetes in adults.

Adults with a body mass index (BMI) between 25 and 29.9 kg/m² are considered overweight. Those with a BMI ≥30 are considered obese. The initial recommendation for any weight loss effort is to achieve a 5-10% reduction in weight, which has been associated with a reduction in the risk of developing type 2 diabetes, hypertension, and dyslipidemia. Diet, exercise, and behavior modification are the preferred methods for losing weight, but long-term weight maintenance can be difficult. Several drugs and devices are FDA-approved for weight reduction and maintenance of weight loss.

View the Comparison Table: Some FDA-Approved Drugs for Weight Management

The FDA has approved fenfluramine oral solution (Fintepla – Zogenix) for treatment of seizures in patients ≥2 years old with Dravet syndrome. It is the third drug to be approved for this indication. Stiripentol (Diacomit) and cannabidiol (Epidiolex), a purified product derived from marijuana, were approved earlier.

The injectable glucagon-like peptide-1 (GLP-1) receptor agonist semaglutide, previously approved by the FDA as Ozempic to treat type 2 diabetes and to reduce the risk of major adverse cardiovascular events in adults with type 2 diabetes and established cardiovascular disease, has now been approved in a higher dose as Wegovy (Novo Nordisk) for chronic weight management in adults with or without type 2 diabetes who have a body mass index (BMI) ≥30 kg/m² or a BMI ≥27 kg/m² and ≥1 weight-related comorbidity (e.g., hypertension, dyslipidemia). An oral formulation of semaglutide (Rybelsus) has been available since 2019 for treatment of type 2 diabetes, but it is not approved for weight management. Liraglutide (Saxenda), another subcutaneously injected GLP-1 receptor agonist, was approved for chronic weight management in 2015.

In recently published clinical trials, once-weekly subcutaneous injection of the glucagon-like peptide 1 (GLP-1) receptor agonist semaglutide (Ozempic – Novo Nordisk), which is FDA-approved for treatment of type 2 diabetes and to reduce the risk of major adverse cardiovascular events in adults with type 2 diabetes and established cardiovascular disease, has reduced body weight significantly in patients with and without type 2 diabetes when given in addition to lifestyle intervention. Liraglutide (Saxenda), another GLP-1 receptor agonist, has been FDA-approved for chronic weight management since 2015.

Adults with a body mass index (BMI) between 25 and 29.9 kg/m2 are considered overweight. Those with a BMI ≥30 are considered obese. The initial recommendation for any weight loss effort is to achieve a 5-10% reduction in weight, which has been associated with a reduction in the risk of developing type 2 diabetes, hypertension, and dyslipidemia. Diet, exercise, and behavior modification are the preferred methods for losing weight, but long-term weight maintenance can be difficult. Several drugs are FDA-approved for weight reduction and maintenance (see Table 1), and procedures such as endoscopic placement of dilated balloons have produced beneficial short-term results (see Table 2), but bariatric surgery has been the most effective intervention for sustainable long-term weight loss and reduction of obesity-related comorbidities.

View the Comparison Table: Some FDA-Approved Drugs for Weight Management

The FDA has approved Lomaira (KVK Tech), an 8-mg tablet formulation of phentermine that can be taken up to three times daily before meals, as an adjunct to lifestyle modifications for weight loss. It is only approved for short-term use (a few weeks) in adults with a body mass index (BMI) ≥30 kg/m², or with a BMI ≥27 kg/m² in addition to a weight-related comorbidity such as hypertension, dyslipidemia, or diabetes. Phentermine has been available alone and in combination with topiramate for years.1

Lomaira was approved by the FDA under an abbreviated new drug application (ANDA) and is considered a generic drug. Its approval was based on the results of earlier phentermine trials. No studies are available comparing the efficacy and safety of Lomaira to standard doses of phentermine or to any other drug approved for weight loss.

Like other sympathomimetic amines approved for weight loss, Lomaira is classified as a schedule IV controlled substance. All sympathomimetics can increase heart rate, raise blood pressure, and cause nervousness and insomnia.2 Phentermine is contraindicated for use in patients with cardiovascular disease, hyperthyroidism, glaucoma, or a history of drug abuse, and in pregnant women. It should not be used while taking, and for 14 days after stopping, a monoamine oxidase (MAO) inhibitor because of the risk of hypertensive crisis.

1. Diet, drugs, and surgery for weight loss. Med Lett Drugs Ther 2015; 57:21.
2. SZ Yanovski and JA Yanovski. Long-term drug treatment for obesity: a systematic and clinical review. JAMA 2014; 311:74.

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Adults with a body mass index (BMI) between 25 and 29.9 kg/m² are considered overweight. Those with a BMI ≥30 are considered obese. Losing even a small amount of weight and increasing physical activity can prevent some of the complications of obesity, particularly type 2 diabetes. Diet and exercise are the preferred methods for losing weight, but long-term failure rates are high. Several drugs have been approved by the FDA for weight reduction, but adherence is poor, adverse effects are common, and patients usually regain the lost weight when the drug is stopped. Bariatric surgery can produce substantial weight loss and significantly reduce obesity-related comorbidities; long-term data on its safety are encouraging, but still limited. Guidelines for the management of overweight or obese adults have recently been published.

The FDA has approved a fixed-dose combination of the opioid receptor antagonist naltrexone (ReVia, and others) and the antidepressant and smoking cessation agent bupropion (Wellbutrin SR, Zyban, and others), as Contrave (Orexigen/Takeda) for weight loss. The combination was approved for use as an adjunct to diet and increased physical activity in patients with a body mass index (BMI) ≥30 kg/m² or a BMI ≥27 kg/m² and one or more weight-related comorbidities such as hypertension, diabetes, or dyslipidemia. Naltrexone/bupropion is not a controlled substance.

In 2013 the FDA approved one new drug and a new combination of 2 old drugs as adjuncts to lifestyle changes for chronic weight management. Lorcaserin (lor-ca-SER-in; Belviq – Arena/Esai) is a selective serotonin 2C receptor agonist. Qsymia (Vivus) is a fixed-dose combination of the weight-loss drug phentermine and an extended-release (ER) formulation of topiramate. The new products are approved for use in obese patients (body mass index [BMI] of ≥30 kg/m²) and for patients who are overweight (BMI ≥27 kg/m²) and have one weight-related risk factor such as hypertension, dyslipidemia or type 2 diabetes.

Adults with a body mass index (BMI=kg/m²) of 25-<30 are considered overweight; those with a BMI of ≥30 are considered obese.

Losing even a small amount of weight and increasing physical activity can prevent some of the complications of obesity, particularly type 2 diabetes. Diet and exercise are the preferred methods for losing weight but are associated with high long-term failure rates. Drugs may help some patients, but all currently available drugs for weight reduction have drawbacks. Gastric surgery can produce marked weight loss in the severely obese, but long-term data on safety are limited.

The latest definitions of overweight and obesity are based on body mass index (BMI). The BMI is calculated by dividing the weight in kilograms by the square of the height in meters (kg/m²). More than half of American adults are considered overweight with a BMI of ≥25, and about one third are obese with a BMI of ≥30. All ages seem to be affected; the proportion of children and adolescents who are overweight has more than doubled in the past 25 years. There is no lack of effort to treat obesity: drugs, diets and programs to change lifestyle are the basis for a large and flourishing industry. The frequent failure of diet and drug treatment sometimes leads to recommendations for surgery, usually restricted to those with a BMI ≥40.

Orlistat, a lipase inhibitor that decreases absorption of fat from the gastrointestinal tract, is now available for treatment of obesity.

Dexfenfluramine (Redux - Wyeth-Ayerst) has been approved by the US Food and Drug Administration as an aid to diet for treatment of obesity and maintenance of weight loss. Dexfenfluramine is the dextrorotatory isomer of d,l-fenfluramine (Pondimin), which has been marketed for short-term weight reduction for many years and recently has been widely used in combination with phentermine (Ionamin, and others), a sympathomimetic drug (Medical Letter, 36:107, 1994).

Recent reports have suggested that some obese patients may benefit from long-term pharmacologic treatment (RL Atkinson and VS Hubbard, Am J Clin Nutr, 60:153, August 1994; DJ Goldstein and JH Potvin, Am J Clin Nutr, 60:647, November 1994). Fluoxetine (Prozac), widely used for treatment of depression and near approval by the US Food and Drug Administration (FDA) for treatment of bulimia, is also being tried for treatment of obesity.