What is the standard Retatrutide dosing protocol?

See the fact-checked Verified Dosing shown at the top of this page (verified against the FDA label / published trials); always confirm with a licensed provider.

How do you reconstitute Retatrutide?

Using 2mL of bacteriostatic water results in a concentration of 2.5mg/mL. Start low and titrate slowly. Always use sterile techniques.

What are the storage requirements for Retatrutide?

Lyophilized (powder): Room temperature or refrigerated, protect from light. Reconstituted: Refrigerated 36-46F (2-8C), use within 30 days.

Retatrutide (LY3437943) — Research Literature Summary

✓ Verified dosing (fact-checked against FDA labels / published trials): Investigational; no FDA-approved dose. Phase 2 (NEJM 2023, NCT04881760): subcutaneous ONCE WEEKLY. Maintenance doses studied = 1, 4, 8, or 12 mg/week. Titration every 4 weeks for tolerability; higher arms started at 2 mg (or 4 mg) and escalated through 4 mg and 8 mg to the 12 mg maintenance dose by roughly week 16-17. Inject once weekly on the same day… This supersedes any conflicting figures shown elsewhere on this page; confirm with a licensed provider.

Class: Investigational triple GIP/GLP-1/glucagon receptor agonist (Eli Lilly) • Page type: research-literature reference • Updated 2026-04-23

Regulatory notice — research reference only

Retatrutide is an investigational compound in Phase 3 clinical trials (TRIUMPH program). It is NOT FDA-approved for any indication and is NOT available through any legitimate compounding or prescribing pathway in the United States. This page describes published clinical-trial dose arms for educational reference only. Not for human use.

Published research summary

Retatrutide (LY3437943) is an Eli Lilly investigational triple agonist at the GIP, GLP-1, and glucagon receptors. It is a 39-amino-acid peptide with a C20 fatty diacid conjugation conferring albumin binding and a half-life of approximately 6 days (weekly subcutaneous dosing).
In the Phase 2 obesity trial (Jastreboff et al., NEJM 2023;389:514-526, PMID 37366315), weekly subcutaneous retatrutide up to 12 mg produced approximately 24% mean body weight reduction at 48 weeks among participants with obesity. In the Phase 2 T2D study (Rosenstock et al., Lancet 2023;402:529-540), HbA1c reductions of up to 2.02% were reported.
The TRIUMPH Phase 3 program includes trials in obesity, obesity with cardiovascular disease, obesity with osteoarthritis, MASH, and heart failure. No Phase 3 efficacy or safety results have been published as of April 2026.
Phase 2 safety signals reported to date include dose-related gastrointestinal adverse events, gallbladder events, heart rate increase (up to ~7 bpm at higher doses), premature ventricular contractions, and standard incretin-class signals (pancreatitis, hypersensitivity). Long-term hepatic safety with chronic glucagon receptor agonism has not been established. The GLP-1 class-wide thyroid C-cell tumor signal (based on rodent studies) applies pending further data.

Why this page does not publish a consumer “cycle” schedule

Retatrutide is investigational. There is no FDA-approved dose, no approved indication, no approved compounding pathway, and no approved prescribing pathway for retatrutide in any jurisdiction as of this writing. Any dosing schedule would represent off-label extrapolation from published trial arms.

Peer-reviewed citations

Jastreboff AM, et al. Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial. NEJM 2023;389:514-526. PMID 37366315.
Rosenstock J, et al. Retatrutide in patients with overweight or obesity and type 2 diabetes: A Phase 2 trial. Lancet 2023;402:529-540.
Sanyal AJ, et al. Retatrutide for MASH (Phase 2). Nature Medicine 2024.
ClinicalTrials.gov - TRIUMPH program (retatrutide, Phase 3).

Consulting a healthcare provider: This page is a reference for published research. If you are considering any health decision, consult a licensed healthcare provider. Path to Peptides does not provide medical advice.

⚠ Before any use: human safety data is limited or absent for many of these compounds. Consult a licensed healthcare provider first — especially if you are pregnant or nursing, have a medical condition, or take other medications.