Not medical advice. Talk to your provider before using any peptide.
Full disclaimerRetatrutide Titration Protocol (Triple G)
Phase 3 trial protocol: weekly titration from 1mg to 12mg. Triple GLP-1/GIP/Glucagon agonist with up to 24% weight loss in clinical trials.
Peptide Schedule Research TeamReviewed Apr 20261 Citation
For maximum weight loss using triple-receptor (GLP-1/GIP/glucagon) activation.
What This Protocol Does
Retatrutide is the first triple agonist, hitting GLP-1, GIP, and glucagon receptors simultaneously. The glucagon component adds direct fat oxidation and energy expenditure on top of appetite suppression. Phase 2 data (n=338) showed up to 24.2% body weight loss at 48 weeks on the 12mg dose, the highest weight reduction reported for any anti-obesity peptide in clinical trials to date.
Who Should Use This
For experienced users who understand GLP-1 titration and want to try the most aggressive weight loss peptide currently in development. Physician supervision is required. Not FDA-approved yet, so access is limited to clinical trials or research settings. Avoid if you have a history of thyroid cancer, pancreatitis, or severe hepatic impairment. The triple-agonist mechanism requires slower titration than single or dual agonists.
What the Research Says
Retatrutide: Phase 2 trial (Jastreboff et al., NEJM 2023, PMID 37351564) enrolled 338 adults with obesity. The 12mg arm achieved 24.2% mean weight loss at 48 weeks. Phase 3 trials (NCT05929066, NCT06246799) are ongoing with results expected in 2025-2026. The glucagon receptor component drives increased resting energy expenditure and hepatic fat reduction (up to 86% liver fat reduction in the Phase 2 NAFLD cohort). GI adverse events occurred in 35-45% of participants.
Important Notices
- Not yet FDA-approved — based on Phase 3 trial protocols
- GI side effects expected during titration
- Titrate slowly — glucagon component adds complexity
Protocol Overview
Dosing Details
| Peptide | Dose | Frequency | Route | Weeks |
|---|---|---|---|---|
| 1mg | Weekly | subcutaneous (abdomen) | Weeks 1-4 | |
| 2mg | Weekly | subcutaneous (abdomen) | Weeks 5-8 | |
| 4mg | Weekly | subcutaneous (abdomen) | Weeks 9-12 | |
| 8mg | Weekly | subcutaneous (abdomen) | Weeks 13-16 | |
RetatrutideMaint. | 12mg | Weekly | subcutaneous (abdomen) | Week 17+ |
Retatrutide: Triple agonist (GLP-1/GIP/Glucagon). Titrate slowly.
Metrics Tracked
Schedule This Protocol
Set your start date and track every dose in your calendar.
Sources & Citations
Peptide Profiles & Calculators
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