Retatrutide GLP-3 RT Dosage Protocols: All Vial Sizes
Retatrutide is a triple-receptor agonist (GLP-1 / GIP / glucagon) studied in Phase 2 trials for body-weight reduction up to 24% at 48 weeks. It is among the most potent incretin compounds in clinical investigation. Choose your vial size below; each size has its own exact dosing table.
Choose Your Vial Size
| Vial | Final volume | Concentration | One U-100 unit | |
|---|---|---|---|---|
| 5 mg | 1 mL | 5 mg/mL | 50 mcg in 0.01 mL | Open protocol → |
| 10 mg | 1 mL | 10 mg/mL | 100 mcg in 0.01 mL | Open protocol → |
| 20 mg | 2 mL | 10 mg/mL | 100 mcg in 0.01 mL | Open protocol → |
| 30 mg | 3 mL | 10 mg/mL | 100 mcg in 0.01 mL | Open protocol → |
| 40 mg | 2 mL | 20 mg/mL | 200 mcg in 0.01 mL | Open protocol → |
| 60 mg | 3 mL | 20 mg/mL | 200 mcg in 0.01 mL | Open protocol → |
Doses are the same research amounts across sizes; the vial size changes the concentration, so syringe units differ. Always use the table for your exact vial.
Storage Instructions
| State | Temperature | Duration |
|---|---|---|
| Lyophilized | −20°C (−4°F) | Up to 24 months, dry & dark |
| Reconstituted | 2–8°C (35–46°F) | Up to 28 days, protect from light |
Important Notes
How This Works
Retatrutide simultaneously activates GLP-1, GIP, and glucagon receptors — the only triple-agonist in clinical trials. GLP-1 activation slows gastric emptying and enhances satiety. GIP augments insulin secretion in response to glucose and modulates lipid metabolism. The glucagon-receptor component drives an increase in energy expenditure absent from dual or single agonists.
The molecule is fatty-acid acylated to bind albumin in serum, slowing renal clearance and enabling once-weekly dosing. The combined three-receptor profile produces greater body-weight reduction in trials than any prior incretin compound.
Potential Benefits & Side Effects
Potential Benefits
- Phase 2 obesity trial: up to 24% weight reduction at 48 weeks (8 mg).
- Phase 2 type-2 diabetes: HbA1c reductions up to 2.0% with substantial weight loss.
- Triple receptor activation drives both appetite suppression and increased energy expenditure.
- Improvements in lipid profile and liver fat content reported alongside weight loss.
Side Effect Profile
- Nausea (most common, dose-dependent — typically resolves with the 4-week titration hold).
- Vomiting and diarrhea, particularly during titration steps.
- Decreased appetite (target effect; can become limiting at higher doses).
- Fatigue and headaches reported during early weeks.
- Heart-rate elevation observed in some trial participants.
Lifestyle Factors
- Hydrate aggressively — incretin agonists slow gastric emptying and reduce thirst signaling.
- Prioritize protein (1.0–1.6 g/kg/day) to preserve lean mass during rapid weight loss.
- Resistance training 2–3×/week is critical to maintain muscle.
- Limit high-fat meals immediately after dosing — fatty foods amplify nausea.
- Smaller, more frequent meals are better tolerated than large meals.
- Sleep 7–9 hours/night — sleep loss blunts GLP-1 efficacy on appetite.
Injection Technique
- Inject subcutaneously into abdomen (avoid 2-inch radius around navel), outer thigh, or upper arm.
- Rotate injection sites every dose to prevent lipohypertrophy.
- 90° angle with short (4–8 mm) insulin syringes.
- Bring vial to room temperature 15 min before injecting.
- Hold 5 seconds after full plunger depression before withdrawing.