Tirzepatide
EstablishedAlso known as Mounjaro, Zepbound
GIP / GLP-1 dual receptor agonist
Two incretin receptors, one injection, up to ~21% body weight gone.
- References
- 3
- Human-grade claims
- 1 of 1
- Evidence floor
- Established
- Status
- Approved
A once-weekly dual agonist that hits both the GIP and GLP-1 receptors. In its pivotal obesity trial it drove weight loss rivaling bariatric surgery, and it is FDA-approved for type 2 diabetes, obesity, and obstructive sleep apnea.
How it works
Tirzepatide activates two gut-hormone receptors at once — GIP and GLP-1 — which together improve insulin response, blunt appetite, and slow gastric emptying. Adding GIP to the GLP-1 effect appears to amplify the metabolic response. A C20 fatty-acid chain gives it a ~5-day half-life.
Sequence: 39-residue GIP-based backbone with Aib at positions 2 and 13, a C20 di-acid on Lys20, and a C-terminal amideA synthetic dual agonist containing non-natural residues and acylation — not representable as plain one-letter code.
What it's studied for
- [1] Jastreboff et al., 2022 (NEJM, SURMOUNT-1)
Produced ~20.9% mean body-weight reduction at 72 weeks on the top dose vs ~3.1% on placebo (SURMOUNT-1).
Established
Safety & limitations
Dose-related gastrointestinal effects (nausea, diarrhea, constipation) predominate. It carries the same class boxed warning for thyroid C-cell tumors and the same MTC/MEN 2 contraindication as GLP-1 agonists.
[2] FDA label — Zepbound (accessdata)Regulatory & legal status
FDA-approved: Mounjaro (type 2 diabetes, 2022) and Zepbound (chronic weight management, 2023; moderate-to-severe obstructive sleep apnea in obesity, 2024).
[2] FDA label — Zepbound (accessdata)Frequently asked
- How is tirzepatide different from semaglutide?
- Semaglutide activates one receptor (GLP-1); tirzepatide activates two (GIP and GLP-1). In trials the dual mechanism has produced larger average weight loss.
References
Written by Twenty Residues editorial. Reviewed by Pending named medical review.
Last updated September 19, 2026.
Update history
- 2026-09-19 — Sourced review — every claim checked against primary literature; sequence, regulatory status, safety, and FAQs added.