In simple terms

A GLP-1 receptor agonist is a medicine that copies the action of GLP-1, short for glucagon-like peptide-1. GLP-1 is a hormone the gut releases after a meal.

These medicines were first used for type 2 diabetes. Some are now also approved for long-term weight management in people with obesity. Well-known examples include semaglutide, sold as Ozempic and Wegovy, and liraglutide.

How it works

An agonist is a drug that switches on a receptor, the part of a cell that a natural hormone normally activates. GLP-1 receptor agonists act on the same receptors as the body’s own GLP-1. Once active, they do several things at once:

• They prompt the pancreas to release insulin when blood sugar is high.
• They reduce glucagon, a hormone that raises blood sugar.
• They slow how fast the stomach empties.
• They act on the brain to reduce hunger and increase the feeling of fullness.

Most are injections given daily or weekly. Semaglutide is also made as a daily tablet.

Why it matters

Obesity affects more than 1 billion people worldwide, according to the World Health Organization. In December 2025, WHO issued a global guideline that conditionally recommends these medicines for long-term obesity treatment in adults, excluding pregnant women. It called the recommendation conditional because long-term evidence is limited and costs are high, and it estimated that fewer than 10% of people who could benefit may have access by 2030.

Approved uses differ by country and regulator. In the United States, for example, semaglutide was approved for type 2 diabetes in 2017 and for chronic weight management in 2021. Common side effects include nausea, vomiting and diarrhea.

Where you’ll see it

• Diabetes and obesity care, where brand names such as Ozempic, Wegovy and Rybelsus are common.
• Health news about research on possible heart and kidney benefits.
• Debates about drug prices and fair global access.
• WHO’s Essential Medicines List, which added GLP-1 therapies for some people with type 2 diabetes in 2025.

Example

The doctor explained that semaglutide is a GLP-1 receptor agonist, so it works by imitating a hormone the gut already makes.

Often confused with

Insulin. Insulin is itself the hormone that lowers blood sugar. A GLP-1 receptor agonist instead prompts the body to release more of its own insulin, mainly when blood sugar is high.

This entry explains a medical term. It is not medical advice. If you are concerned about your health, speak with a qualified health professional.

Editorially reviewed by Specialty Digest Editorial TeamLast reviewed September 11, 2026Researched and drafted with AI assistanceReport an issue