Retatrutide
Also known as: LY3437943
Retatrutide is a popular peptide topic online, but it is not FDA-approved for human use. Use this guide to understand the claims, the evidence gaps, and the safety questions to ask before considering anything further.
Phase 2 trials showed 24.2% weight loss at the highest dose, and early Phase 3 topline updates have been positive. The broader Phase 3 program is still in progress, so approval timing and labeling remain uncertain.
What to know before you go deeper
Triple agonist: GLP-1 + GIP + Glucagon receptors. The glucagon component adds significant fat-burning beyond dual agonists like tirzepatide.
Approval status: Not FDA-approved. This is not an FDA-approved human treatment.
Weight loss (potentially 25%+ body weight), Type 2 diabetes, NASH/MASH liver disease.
What evidence applies to my situation, what monitoring is needed, and what safer first steps should I try?
Why People Ask About Retatrutide
- Weight loss (potentially 25%+ body weight)
- Type 2 diabetes
- NASH/MASH liver disease
Questions to Bring Up
Clinical-trial medication only. There is no approved commercial dose or consumer treatment plan.
Dosing, sourcing, and suitability questions belong with a licensed clinician who can review your history, labs, medications, and goals.
Known Side Effects
- Nausea
- Diarrhea
- Vomiting
- Similar to semaglutide/tirzepatide profile
Important Safety Notes
Not commercially available — only through clinical trials
Watch eli.lilly.com for trial enrollment
Potential next-generation GLP-1 class drug if approved
What Is Approved?
Phase 3 clinical trials are active in 2026. Retatrutide is not FDA approved, and Lilly has indicated a potential regulatory submission could come after additional late-stage results.
Your feedback helps us improve the guide.