Is Tirzepatide a GLP-1? It Is a GLP-1 and a GIP

Short answer: tirzepatide is a GLP-1 medication and more. It is a dual agonist: it activates both the GLP-1 receptor and the GIP receptor (glucose-dependent insulinotropic polypeptide). Semaglutide activates only the GLP-1 receptor.

What "dual agonist" means

GLP-1 and GIP are both natural gut hormones released after eating. Each affects insulin release and appetite signaling. Tirzepatide is engineered to activate both receptors, which is why the FDA labels describe it as a GIP receptor and GLP-1 receptor agonist. Because it acts on GLP-1, people commonly group it with GLP-1 medications.

How it differs from semaglutide

Semaglutide (Ozempic, Wegovy) is a GLP-1 receptor agonist only. In the head-to-head SURMOUNT-5 trial in adults with obesity, tirzepatide produced 20.2% average weight loss versus 13.7% for semaglutide at 72 weeks. Researchers often attribute part of the difference to the dual mechanism, though the drugs also differ in other ways.

Should you use them together?

No. The Zepbound label says that using it together with other tirzepatide-containing products or with any GLP-1 receptor agonist is not recommended.