A dual GIP/GLP-1 receptor co-agonist (Mounjaro/Zepbound) with the strongest weight-loss data of any approved agent to date.
FDA and EMA approved — Mounjaro for type 2 diabetes (May 2022) and Zepbound for chronic weight management (November 2023). A prescription drug, not investigational.
Also known as: Mounjaro, Zepbound, LY3298176
Activates two incretin receptors at once: the GLP-1 arm boosts insulin, suppresses glucagon, slows gastric emptying and increases satiety; the GIP arm adds effects on insulin sensitivity and adipose fat handling, acting synergistically.
In SURMOUNT-1, mean weight loss at 72 weeks was about 15-21% across doses versus ~3% on placebo. The SURPASS diabetes programme showed strong HbA1c and weight reductions, and SURMOUNT-4 demonstrated continued loss with maintenance versus regain after switching to placebo. In the SURMOUNT-5 head-to-head it beat semaglutide (~20% vs ~14% at 72 weeks). Limitations: weight regain on discontinuation, GI-driven dropout, and cardiovascular-outcome data that matured later than semaglutide's.
We report both positive and negative trial results. For exact study protocols, read the sources — we cite them rather than repackage them.
Bars reflect the strength & volume of research evidence for each use — not a guarantee of results.
Predominantly gastrointestinal — nausea, diarrhoea, vomiting, constipation — mostly during dose escalation. Gallbladder events, pancreatitis risk and a rodent thyroid C-cell tumour signal (boxed warning) mirror the GLP-1 class.
Semaglutide and retatrutide — compared within the incretin class rather than combined. Insulin and metformin in diabetes. Its dual GIP + GLP-1 agonism is why it is benchmarked against single GLP-1 agonists.
Mechanistic context only — we don't publish combinations, amounts or protocols.
Versus semaglutide (GLP-1 only), tirzepatide adds GIP-receptor agonism and produces greater average weight loss. Versus retatrutide (triple agonist) it lacks the glucagon arm and shows somewhat lower peak weight loss in cross-trial comparison.
No. It is a different molecule — a dual GIP/GLP-1 agonist rather than GLP-1 only. It outperformed semaglutide head-to-head, but the mechanisms differ rather than it simply being a higher dose.
The added benefit is associated with dual agonism, but exactly how GIP contributes to appetite and energy expenditure in humans is still incompletely understood.
No. Trials show significant regain after stopping, so it is studied as an ongoing treatment.
No reviews yet. If you've used Tirzepatide, be the first to share what it helped with and any side effects.
⚠️ Educational research information only — not medical advice. Many peptides are sold strictly for laboratory research and are not approved treatments. The evidence scores reflect research interest and strength, not efficacy or safety for any individual. Always consult a qualified professional.