Semaglutide vs tirzepatide: how GLP-1 medications compare

The two active ingredients behind the best-known GLP-1 brand names, and what actually separates them.

Behind the brand names — Ozempic®, Wegovy®, Mounjaro®, Zepbound® — there are really two active ingredients in wide use: semaglutide and tirzepatide. Understanding the difference between the ingredients is more useful than memorizing which brand is which.

Semaglutide is a GLP-1 receptor agonist. It mimics a hormone your gut releases after eating, which is involved in signalling fullness and in regulating blood sugar. Ozempic® and Wegovy® both contain semaglutide.

Tirzepatide acts on that same GLP-1 pathway and additionally on a second one, GIP. That is why it is often called a dual agonist. Mounjaro® and Zepbound® both contain tirzepatide.

Acting on two pathways instead of one is a real pharmacological difference, but it does not translate into a simple better-or-worse verdict for any individual. Tolerability, medical history, other medications, and what a clinician is actually treating all factor in. Some people do better on one than the other, and there is no way to know from a search result which that will be.

Both classes are once-weekly injections, both start at a low dose and increase gradually, and both are prescription-only. A licensed clinician reviews your assessment and recommends an approach, or explains why treatment is not appropriate.

This article is educational and is not a substitute for personalized medical advice. Whether any medication is appropriate for you is a decision for a licensed clinician who has reviewed your health history.