GLP-1 Agonists for Weight Loss

Reviewed by: HU Medical Review Board | Last reviewed: June 2023

A glucagon-like peptide-1 (GLP-1) agonist is a type of drug used for the treatment of type 2 diabetes. More recently, GLP-1 agonists have been used for weight loss and weight management.1,2

How do GLP-1 agonists work?

GLP-1 agonists mimic the GLP-1 hormone. This hormone regulates appetite and food intake. When used for weight loss, GLP-1 agonists work by reducing appetite, increasing feelings of fullness, and slowing down the movement of food through the stomach. This leads to a reduced calorie intake, which can in turn result in weight loss.1,2

GLP-1 agonists are typically prescribed to those who have a body mass index (BMI) of 30 or higher, or a BMI of 27 or higher with obesity-related health conditions such as high blood pressure, type 2 diabetes, or dyslipidemia. They are usually prescribed with a healthy diet and regular exercise.1,2

Examples of GLP-1 agonists

Several GLP-1 agonists have been approved by the US Food and Drug Administration (FDA) to treat type 2 diabetes as well as obesity. These medicines are given as injections. The dosage depends on the person and the specific drug. Weight loss may vary depending on which GLP-1 drug you use and the dose you take.1-4

Examples of GLP-1 agonists include the following.

Liraglutide (Saxenda®)

Saxenda is FDA-approved for the treatment of adults with type 2 diabetes. Saxenda is also FDA-approved at a higher dose for adults with obesity and at least 1 weight-related health condition (high blood pressure, type 2 diabetes, dyslipidemia).1-4

For more information, read the full prescribing information of Saxenda.

Semaglutide (Ozempic® and Wegovy®)

Wegovy and Ozempic are both FDA-approved for use in adults with type 2 diabetes as well as people with obesity. They are available in oral and injection forms for the treatment of type 2 diabetes. They are only available in injection form for the treatment of obesity.1-3,5,6

Ozempic is not approved for use in people under the age of 18.5

Wegovy is available for children ages 12 and older who have a BMI at the 95th percentile or greater for their age and gender.6

For more information, read the full prescribing information of Ozempic and the full prescribing information of Wegovy.

Tirzepatide (Mounjaro™)

Tirzepatide is FDA-approved for use in adults with type 2 diabetes. It is effective at achieving weight loss in people with and without type 2 diabetes. But at this time, it has not been FDA-approved for use in the treatment of obesity.1,7

For more information, read the full prescribing information of Mounjaro.

What are the possible side effects?

Side effects can vary depending on the specific drug you are taking. The most common side effects of GLP-1 agonists are:1-6

  • Nausea
  • Vomiting
  • Diarrhea
  • Abdominal pain
  • Constipation
  • Low blood sugar levels (hypoglycemia)

These are not all the possible side effects of GLP-1 agonists. Talk to your doctor about what to expect when taking GLP-1 agonists. You also should call your doctor if you have any changes that concern you when taking a GLP-1 agonist.

Saxenda, Wegovy, Ozempic, and Mounjaro all have a boxed warning, the strictest warning from the FDA. They have this warning because these drugs can cause thyroid C-cell tumors. Therefore, people with a personal or family history of thyroid cancer or multiple endocrine neoplasia should not use these drugs.4-7

Other things to know

GLP-1 agonists are not recommended for people who have had pancreatitis. Also, do not take these drugs if you are pregnant or planning to become pregnant, as they could harm the unborn baby.2,4-7

Before beginning treatment for obesity, tell your doctor about all your health conditions and any other drugs, vitamins, or supplements you take. This includes over-the-counter drugs.

Talk with your doctor

GLP-1 agonists for weight loss should be taken only under the guidance and prescription of a healthcare professional. Talk with your doctor about whether GLP-1 agonists are right for you.

By providing your email address, you are agreeing to our privacy policy.