GLP-1 medications
GLP-1 vs GLP-2: two gut hormones, different jobs
October 6, 2026 · 5 min read · Medically reviewed by Bryan Milton, MD · Reviewed October 6, 2026
GLP-1 and GLP-2 come from the same gut cells but do different things. What each hormone does, which medications act on them, and where GIP fits.
The names suggest a sequence, as if GLP-2 were a newer or stronger version of GLP-1. It is not. GLP-1 and GLP-2 are separate hormones that happen to be cut from the same larger protein, and they do largely different jobs. The difference matters because people looking for the next GLP-1 sometimes land on GLP-2 products, research peptides or claims that do not hold up.
Where do GLP-1 and GLP-2 come from?
Both are made by L cells, hormone-producing cells in the lining of the intestine. These cells make a precursor protein called proglucagon and cut it into several smaller peptides, including GLP-1 and GLP-2, which are released into the bloodstream after you eat. In the pancreas, the same precursor is cut differently to make glucagon, the hormone that raises blood sugar. That shared origin is where the 'glucagon-like' in both names comes from.
What does GLP-1 do?
GLP-1 acts on several organs at once. It prompts the pancreas to release insulin when blood sugar is high and to release less glucagon, slows how quickly the stomach empties, and acts on areas of the brain involved in appetite and fullness. Those effects are why it became the basis for medications for type 2 diabetes and, later, weight management.
What does GLP-2 do?
GLP-2 acts mainly on the gut itself. It stimulates growth of the lining of the small intestine, increases blood flow to it, strengthens the barrier the lining forms, and helps the intestine absorb nutrients. It is not part of how GLP-1 medications affect appetite or blood sugar, and it is not a weight-management treatment.
| GLP-1 | GLP-2 | GIP | |
|---|---|---|---|
| Made in | L cells of the intestine | L cells of the intestine | K cells of the upper small intestine |
| Main actions | Insulin release, slower stomach emptying, fullness signals | Growth and absorption of the intestinal lining | Insulin release after meals |
| Medications that act on it | GLP-1 receptor agonists, such as semaglutide and liraglutide; tirzepatide | Teduglutide, a GLP-2 analogue | Tirzepatide, together with GLP-1 |
| What those medications are approved for | Type 2 diabetes, chronic weight management and other uses | Short bowel syndrome | Type 2 diabetes, chronic weight management, obstructive sleep apnea |
Are there GLP-2 medications?
One is approved in the US: teduglutide, a 33-amino-acid GLP-2 analogue given by injection. It has been approved since 2012 for adults and children aged 1 and older with short bowel syndrome who depend on nutrition or fluids given into a vein. It helps the remaining intestine absorb more, so that some people need less of that support. It is a specialist treatment and has no approval for weight loss.
Is tirzepatide a GLP-2?
No. Tirzepatide acts on the receptors for GLP-1 and for GIP, glucose-dependent insulinotropic polypeptide. GIP is a separate gut hormone, made by K cells higher up the small intestine, that also prompts insulin release after meals. That is why tirzepatide is called a dual agonist, and its molecule is built on the GIP sequence. Nothing in it acts on GLP-2.
What about medications that act on more hormones?
Molecules that act on several of these hormones at once, including combinations with glucagon, are in development. Treat anything sold online under the name of an unapproved molecule with suspicion: a vial labelled 'research peptide' is not a prescription medicine, whatever it claims to contain. Our article on research-use peptides explains the risks.
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.