Retatrutide: Benefits, Dosage & FDA Status
Retatrutide (LY3437943)
Triple agonist at GLP-1, GIP, and glucagon receptors. Phase 2 produced 24.2% mean weight reduction at 48 weeks — the highest ever in a clinical obesity trial.
FDA Status
Not FDA-approved — Phase 3 trials (TRIUMPH program) for obesity
Typical Dose
Trial range: 1–12 mg weekly (subcutaneous)
Evidence Grade
AStrong RCT or FDA-approved evidence
Half-Life
~6 days (estimated)
Routes of Administration
subcutaneous
First Synthesized
2022
Clinics Indexed
12 providers have offered Retatrutide in our tracked directory.
Mechanism of Action
Triple agonist at GLP-1, GIP, and glucagon receptors — combines incretin appetite/glucose actions with glucagon-mediated energy expenditure.
Key Reported Benefits
- ✓Highest reported weight loss
- ✓Triple incretin/glucagon mechanism
- ✓Metabolic improvement
Benefits listed reflect commonly reported effects from clinical trials and practitioner use. Individual response varies. Evidence-grade A indicates strong rct or fda-approved evidence.
Reported Side Effects
- •Nausea
- •Vomiting
- •Diarrhea
- •Heart-rate increase
Contraindications
- ⚠Personal/family history of medullary thyroid carcinoma
- ⚠Pregnancy
Regulatory & Safety Context
FDA status: Not FDA-approved — Phase 3 trials (TRIUMPH program) for obesity
This page is for educational purposes only and does not constitute medical advice. Peptide use outside of an FDA-approved indication should be discussed with a licensed medical professional. Source quality, cold-chain storage, and injection hygiene all materially affect safety outcomes.
See state-by-state legality: US peptide legality by state →
References
Selected primary literature on Retatrutide. Full PubMed records linked. Additional citations are available on request.
Last reviewed: 2026-04-30
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