Semaglutide
Ozempic / Wegovy / RybelsusRCSB PDB 7KI0 · 3D model
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A lab-made copy of a gut hormone that attaches to its natural receptor, prompting the pancreas to release insulin, slowing digestion, and signaling the brain to reduce hunger and food intake.
How it works
Semaglutide is a lab-made copy of a natural gut hormone called GLP-1, engineered with a chemical tag that lets it stick to a blood protein so it stays active for about a week instead of minutes. It locks onto the same receptor the natural hormone uses, telling the pancreas to release more insulin and less of a hormone called glucagon, but only when blood sugar is high — which lowers blood sugar without a big risk of it dropping too low. It also acts on appetite centers in the brain and slightly slows how fast the stomach empties, both of which make people feel fuller and eat less. Together, these effects explain why the drug helps control blood sugar and also leads to meaningful weight loss. As Rybelsus, the same drug comes as a pill instead of a shot: since stomach acid would normally destroy a protein-based drug like this one, the tablet is combined with an ingredient called SNAC that briefly changes the chemistry right around the pill, letting enough of the drug slip through the stomach lining before it's digested away.
What it’s used for
As Ozempic, this drug is approved to help adults with type 2 diabetes manage their blood sugar, lower their risk of heart attack, stroke, and cardiovascular death if they already have heart disease, and slow kidney damage if they have diabetes-related kidney disease. As Wegovy, the same medicine at a higher dose is approved to help adults and teens (12 and up) with obesity, or overweight adults with a weight-related health condition, lose weight and keep it off, and to lower cardiovascular risk in adults with heart disease and obesity or overweight — always alongside diet and exercise changes. As Rybelsus — sold under that name outside the US, and increasingly as "Ozempic tablets" within the US since 2026 — it's used the same way as the Ozempic injection to control blood sugar and lower cardiovascular risk, just in pill form, and isn't approved for weight loss; because the pill's absorption trick only works on an empty stomach, it has to be taken first thing in the morning with a small sip of water, waiting at least 30 minutes before eating, drinking, or taking other medications. A newer oral pill sold as Wegovy was separately approved in December 2025 specifically for weight loss.
- Mechanism
- GLP-1 receptor agonist (peptide analog)
- Drug class
- Peptide analog
- Therapeutic area
- Metabolic / Diabetes / Weight Management