Semaglutide is a GLP-1 receptor agonist — a medication that mimics the gut hormone GLP-1 to reduce appetite, slow stomach emptying, and improve blood sugar. It's the active ingredient in Ozempic (approved for type 2 diabetes) and Wegovy (approved for chronic weight management).
A related, newer medication is tirzepatide (Mounjaro/Zepbound), which acts on both GLP-1 and GIP. These are prescription medicines that require a clinician's assessment; see how they work and their side effects.