View the Table: GLP-1 and GIP/GLP-1 Receptor Agonists for Chronic Weight Management

The injectable glucose-dependent insulinotropic polypeptide (GIP)/glucagon-like peptide-1 (GLP-1) receptor agonist tirzepatide, which was approved by the FDA as Mounjaro for treatment of type 2 diabetes in 2022, has now been approved as Zepbound (Lilly) for chronic weight management in adults who have a BMI ≥30 kg/m² or a BMI ≥27 kg/m² and at least one weight-related comorbidity. The injectable GLP-1 receptor agonists liraglutide (Saxenda) and semaglutide (Wegovy) are approved for chronic weight management in patients ≥12 years old.

Glucagon-like peptide-1 (GLP-1) receptor agonists and the dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 receptor agonist tirzepatide (Mounjaro) are widely prescribed for treatment of type 2 diabetes and weight management (see Table 1), but they delay gastric emptying and commonly cause nausea and vomiting. Gastroparesis and bowel obstruction (ileus) have also been reported with their use.

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.

Diet, exercise, and weight loss can improve glycemic control, but almost all patients with type 2 diabetes require antihyperglycemic drug therapy. Treating to a target A1C of <7% while minimizing hypoglycemia is recommended to prevent microvascular complications of diabetes (retinopathy, nephropathy, and neuropathy). An A1C target of <8% may be appropriate for some older patients.

The FDA has approved tirzepatide (Mounjaro – Lilly), a peptide hormone with activity at both glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors, to improve glycemic control in adults with type 2 diabetes. Tirzepatide, which is injected subcutaneously once weekly, is the first dual GIP/GLP-1 receptor agonist to become available in the US. Selective GIP receptor agonists are not available in the US; GLP-1 receptor agonists have been available for years.

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 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 injectable glucagon-like peptide-1 (GLP-1) receptor agonist liraglutide, previously approved by the FDA for treatment of type 2 diabetes as Victoza, has now also been approved at a higher dose as Saxenda (Novo Nordisk) for chronic weight management in adults with a BMI ≥30, or a BMI ≥27 with a weight-related comorbidity such as hypertension, dyslipidemia, or diabetes.

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.