How to Reconstitute Retatrutide: 5mg, 10mg and 15mg Vials
Reference guide. Next Day Pharma supplies pre-filled, ready-to-use injection pens — there is nothing to mix, and no vials, powder or bacteriostatic water are involved. This article is published as general reference information only.
Retatrutide is a triple-receptor agonist (GLP-1, GIP and glucagon) supplied as lyophilised powder. Reconstitution is virtually identical to tirzepatide, but the higher commonly-used doses mean the BAC water volume matters more for syringe accuracy.
Recommended reconstitution ratios
| Vial size | BAC water | Concentration |
|---|---|---|
| 5 mg | 1.0 ml | 5 mg/ml |
| 10 mg | 2.0 ml | 5 mg/ml |
| 15 mg | 3.0 ml | 5 mg/ml |
Keeping a 5 mg/ml concentration across vial sizes means the same insulin-syringe units always equal the same dose.
Reconstitution steps
- Allow both vials to reach room temperature.
- Wipe both rubber stoppers with alcohol swabs.
- Draw the correct BAC water volume into a 3 ml syringe.
- Insert the needle into the retatrutide vial at an angle; let the water run down the glass — do not spray directly onto the powder.
- Swirl gently until fully dissolved.
- Date the vial and refrigerate at 2–8°C.
Retatrutide dose chart (5 mg/ml concentration)
| Weekly dose | Volume | Insulin syringe units |
|---|---|---|
| 1 mg | 0.20 ml | 20 units |
| 2 mg | 0.40 ml | 40 units |
| 4 mg | 0.80 ml | 80 units |
| 6 mg | 1.20 ml | 2 × 60 units |
| 8 mg | 1.60 ml | 2 × 80 units |
| 12 mg | 2.40 ml | 3 × 80 units |
For odd vial volumes, our dose calculator handles the conversion.
Storage
2–8°C in the fridge, away from the door and the back wall. Stable for 28 days. Discard if cloudy or after the 28-day window.
Frequently asked questions
Is retatrutide stronger than tirzepatide?
Retatrutide acts on three receptors (GLP-1, GIP, glucagon) versus tirzepatide's two, so research shows greater effect sizes at equivalent doses. See our comparison guide.
How much BAC water for a 10mg retatrutide vial?
2 ml gives a clean 5 mg/ml mix where 100 units = 5 mg.
How long does reconstituted retatrutide last?
28 days refrigerated at 2–8°C.
Where can I buy retatrutide in the UK?
See our retatrutide product page — UK stock, free next-day delivery.
This guide is provided for informational purposes by Next Day Pharma. All peptides supplied are FOR RECONSTITUTION. Always consult a qualified healthcare professional before use.