GLP-1 medications are a class of injectable (and one oral) drugs that mimic a gut hormone called glucagon-like peptide-1. They were originally developed for type 2 diabetes, but turned out to cause substantial weight loss as a side effect — so substantial that several are now FDA-approved specifically for chronic weight management.
The short version
- They are synthetic versions of a hormone your gut already makes after meals.
- They lower blood sugar, slow digestion, and reduce appetite.
- The newest generation (tirzepatide) also activates a second hormone receptor (GIP) and is more powerful.
- They work for as long as you take them — stopping usually leads to weight regain.
The drugs in this class
| Brand | Generic | Indication |
|---|---|---|
| Ozempic | semaglutide | Type 2 diabetes |
| Wegovy | semaglutide | Weight management |
| Rybelsus | semaglutide (oral) | Type 2 diabetes |
| Mounjaro | tirzepatide | Type 2 diabetes |
| Zepbound | tirzepatide | Weight management |
| Saxenda | liraglutide | Weight management |
| Victoza | liraglutide | Type 2 diabetes |
| Trulicity | dulaglutide | Type 2 diabetes |
Tirzepatide is technically a dual GLP-1 / GIP agonist rather than a pure GLP-1, but it is conventionally grouped with the class.
Why the buzz?
Two reasons:
- Weight loss is real and substantial. Average weight loss with semaglutide in the STEP trials was ~15% of body weight. Tirzepatide hit ~21% in SURMOUNT-1 — territory previously only seen with bariatric surgery.
- Health outcomes are improving too. The SELECT trial showed semaglutide reduced major cardiovascular events by 20% in adults with obesity and existing heart disease. Renal benefits (FLOW), sleep apnea improvements, and even reduced alcohol cravings are emerging in newer data.
What they aren’t
- Not a cure. Stop the drug and the appetite suppression stops with it.
- Not for everyone. People with a history of medullary thyroid cancer, MEN 2 syndrome, pancreatitis, or severe gastroparesis should avoid them.
- Not free of side effects. Nausea is near-universal during dose escalation, and rare-but-serious side effects exist.
Next steps
- Read how GLP-1s actually work in the body.
- Check the 2026 rankings to see which drug fits your situation.
- Learn how to get a prescription without falling for counterfeit suppliers.
Educational content only — not medical advice. Always consult a licensed clinician before starting or changing GLP-1 therapy.