Information only. Not medical advice, and not a recommendation to use any compound. We do not sell or supply any compound Speak to a doctor before any decision about your health Information only. Not medical advice, and not a recommendation to use any compound. We do not sell or supply any compound Speak to a doctor before any decision about your health Information only. Not medical advice, and not a recommendation to use any compound. We do not sell or supply any compound Speak to a doctor before any decision about your health
Genexis Health
Compounds
Metabolic Mounjaro · Zepbound

Tirzepatide

Also known as GIP/GLP-1 dual agonist · developed by Eli Lilly

Approved medicine

Licensed by at least one major regulator for a specific indication, on the strength of completed phase 3 trials. Approval is for that indication in that population — it is not a general endorsement of the compound.

Prescription medicine Licensed and available only on prescription in the UK, EU and US. Supply without a prescription is illegal.
Illustration only. Not a photograph of a product, and not an offer of supply — Genexis Health does not sell or supply Tirzepatide.

What it is

A single molecule that activates two incretin receptors — GIP and GLP-1 — built on a GIP backbone with substitutions that resist degradation and a fatty acid chain for weekly dosing.

How it is thought to work

Dual agonist at GIP and GLP-1 receptors. The contribution of GIP agonism is still debated: it improves insulin sensitivity and may reduce the nausea burden relative to GLP-1 alone, but the mechanism behind the larger weight effect is not settled.

What the studies found

  • Larger weight reduction than GLP-1 alone

    SURMOUNT-1 reported mean weight loss around 21% at 72 weeks at the highest dose. SURMOUNT-5, a head-to-head against semaglutide, found greater reduction with tirzepatide (approximately 20% versus 14%).

  • Strong glycaemic effect

    The SURPASS programme showed HbA1c reductions exceeding comparators including insulin and semaglutide in type 2 diabetes.

  • Obstructive sleep apnoea

    SURMOUNT-OSA reported reductions in apnoea-hypopnoea index, leading to an additional licensed indication.

What the evidence does not show

  • Cardiovascular outcome data is less mature than semaglutide's — SURPASS-CVOT reported non-inferiority to dulaglutide rather than the event reduction SELECT showed.
  • As with semaglutide, weight is regained after discontinuation.
  • The relative contribution of GIP versus GLP-1 agonism remains an open scientific question.

Reported risks and adverse effects

  • Gastrointestinal effects dominate: nausea, diarrhoea, vomiting, constipation, most common during escalation.
  • Same rodent thyroid C-cell finding and the same contraindication as semaglutide.
  • Pancreatitis and gallbladder disease reported.
  • Hypoglycaemia risk rises when combined with insulin or sulfonylureas.

This is a summary of what has been reported in the literature, not a complete safety profile. For anything concerning your own health, speak to a doctor.

Regulatory status

Licensed for type 2 diabetes (Mounjaro) and weight management and OSA (Zepbound). Prescription-only in the UK, EU and US.

Related

More in Metabolic & incretin

Semaglutide

Approved

A long-acting analogue of GLP-1, a hormone the gut releases after eating. Structural changes — an Aib substitution that …

Retatrutide

Phase 3

An investigational agonist at three receptors — GIP, GLP-1 and glucagon. The glucagon component is what distinguishes it…

AOD-9604

Failed trials

A fragment of the C-terminus of human growth hormone, developed specifically as a weight-loss drug on the theory that th…