Retatrutide: which line to draw to
Enter your Retatrutide vial amount, the water you added and your dose. Retatrutide is dosed in mg; the syringe shows exactly where to stop. New to this?
Your line shows up here.
Fill in the vial, water and dose boxes.
Investigational. In phase 3 trials; not approved anywhere.
Retatrutide at a glance
- Evidence
- Investigational. In phase 3 trials; not approved anywhere.
- Vial sizes
- 10, 15 mg
- Usual dose range
- 1–12 mg
- How often
- Weekly
- Unmixed
- Freezer −20°C
- After mixing
- Fridge 2–8°C, use within 30 days
Retatrutide units to mg chart
Syringe units on any U-100 insulin syringe (100 units = 1 mL), worked out by the same engine as the calculator. Your own vial and water may differ: use the calculator for your numbers.
| Dose | Units | mL |
|---|---|---|
| 1 mg | 10 | 0.1 |
| 2 mg | 20 | 0.2 |
| 4 mg | 40 | 0.4 |
| 8 mg | 80 | 0.8 |
| 12 mg | More than the vial holds | |
| Dose | Units | mL |
|---|---|---|
| 1 mg | 10 | 0.1 |
| 2 mg | 20 | 0.2 |
| 4 mg | 40 | 0.4 |
| 8 mg | 80 | 0.8 |
| 12 mg | More than a 1 mL syringe | |
Retatrutide questions
How many units is 1 mg of Retatrutide?
With a 10 mg vial mixed with 1 mL of bacteriostatic water, 1 mg is 10 units (0.1 mL) on a U-100 insulin syringe. A different vial size or amount of water changes this, so check it with your own numbers.
How much water do I add to a 10 mg Retatrutide vial?
1 mL of bacteriostatic water is common, which makes 10 mg per mL. More water makes each dose a bigger amount that is easier to measure; it doesn't change how much is in the vial.
How long does mixed Retatrutide last?
Once mixed, keep it at fridge temperature, 2–8°C and use it within 30 days. Unmixed powder: freezer −20°c.
What is Retatrutide?
Retatrutide (LY3437943) is an investigational drug from Eli Lilly that acts on three hormone receptors: GLP-1, GIP and glucagon. It wasn’t approved anywhere when this page was last reviewed, and a vial bought online is not the trial drug.
Trial results
In a phase 2 trial published in 2023, people on 12 mg a week lost about 24% of their body weight on average over 48 weeks. Larger phase 3 trials (the TRIUMPH programme) decide whether it gets approved; their status is listed on ClinicalTrials.gov.
Strong vials, small doses
Vials sold online are often mixed strong, around 10 mg per mL, which makes small doses only a few units: 1 mg is 10 units. Adding more water makes small doses easier to measure accurately.
What isn’t known
Long-term safety isn’t known yet. Unregulated products can contain the wrong amount, a different substance or contamination, and nobody checks.
Sources
- Jastreboff AM et al. Triple-Hormone-Receptor Agonist Retatrutide for Obesity. N Engl J Med, 2023.