Retatrutide
Triple agonist: GIP/GLP-1/Glucagon receptor agonist. Eli Lilly. Most potent weight loss peptide in clinical trials. Phase 3 trials ongoing.
Overview
Triple agonist: GIP/GLP-1/Glucagon receptor agonist. Eli Lilly. Most potent weight loss peptide in clinical trials. Phase 3 trials ongoing.
Profound appetite suppression, improves fasting glucose and HbA1c, may improve lipid profile more than dual agonists (glucagon component increases energy expenditure), can elevate amylase/lipase, increased heart rate reported, may affect liver enzymes
Compound Guide
Structure: Triple-acting peptide agonist at GIP, GLP-1, and Glucagon receptors. The glucagon receptor activation is unique — increases energy expenditure and hepatic fat oxidation on top of the appetite suppression from GIP/GLP-1.
Dosage:
- Clinical trial dosing: 1mg/week → 2mg/week → 4mg/week → 8mg/week → 12mg/week (titrated monthly)
- Bodybuilding use: Limited data — most users start at 1-2mg/week and titrate based on response
Administration:
- SubQ injection once weekly
- Titrate slowly over weeks/months
Key Notes:
- Phase 3 clinical trials ongoing — not yet FDA-approved (as of 2025)
- Clinical trials showed up to 24% body weight loss at 48 weeks (most potent of any GLP-1 class drug)
- Glucagon receptor activation differentiates it: increases energy expenditure, promotes hepatic fat oxidation
- Triple mechanism may reduce liver fat (NAFLD/NASH) more effectively than dual agonists
- GI side effects expected to be similar to other GLP-1 agonists
- Resting energy expenditure increase from glucagon component is unique and potentially muscle-sparing
- Very limited real-world bodybuilding data — early adopters only
- Monitor: fasting glucose, HbA1c, lipid panel, liver enzymes, amylase/lipase, heart rate
Usage History
Frequently Asked Questions
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Quick Reference
Category
GLP-1
Half-Life
~6 days
Detection Time
N/A