Overview
Tirzepatide is a dual GIP/GLP-1 receptor agonist developed by Eli Lilly. It targets both glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors, producing greater weight loss than GLP-1-only agonists like semaglutide. Approved as Mounjaro (diabetes) and Zepbound (obesity).
Mechanism of action
Dual agonism: activates both GIP and GLP-1 receptors. GLP-1 receptor activation reduces appetite and slows gastric emptying. GIP receptor activation enhances insulin sensitivity and may improve fat metabolism. The dual mechanism produces synergistic effects exceeding either pathway alone.
Dosing protocols
| Purpose | Route | Dosage | Frequency | Notes |
|---|---|---|---|---|
| weight loss | subcutaneous | 2.5–15 mg | weekly | Start 2.5mg weekly for 4 weeks, escalate every 4 weeks: 5 → 7.5 → 10 → 12.5 → 15mg. |
Dosing information is for educational purposes only. Consult a qualified healthcare professional before using any peptide.
Research summary
SURMOUNT trials demonstrated 22.5% body weight reduction (15mg dose, 72 weeks) — the highest weight loss achieved by any pharmaceutical in clinical trials. FDA-approved for T2D (Mounjaro) and obesity (Zepbound). Head-to-head trials show superiority over semaglutide for weight loss.
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with Tirzepatide for synergistic effects.
Legal status
FDA-approved as Mounjaro (diabetes) and Zepbound (obesity). Prescription only. Supply shortages ongoing in 2026.
Where to get it
Prescription required
Tirzepatide is a prescription medication. Consult your healthcare provider or a licensed telehealth platform for access.