Dual GIP/GLP-1 receptor agonist
Reconstitute injectable tirzepatide from a lyophilized vial and get the units to draw. Mounjaro and Zepbound are the prefilled-pen forms of tirzepatide; this calculator is for the lyophilized vials that you reconstitute yourself. Enter your vial strength in mg, bacteriostatic water volume, and weekly dose for the mark on a U-100 insulin syringe.
Draw to
Draw to the 12.5 unit mark. That is 0.125 mL of solution.
Informational and educational only. Not medical advice. This tool performs math on values you enter and is not a substitute for your prescriber.
The titration schedule from the prescribing label or published trials, shown for reference, not a recommendation. Follow your prescriber. Units to draw are calculated from your current vial and water settings above and update live.
| Period | Dose | Draw (units) | Volume |
|---|---|---|---|
| Weeks 1-4current | 2.5 mg | 12.5 | 0.125 mL |
| Weeks 5-8 | 5 mg | 25 | 0.250 mL |
| Weeks 9-12 | 7.5 mg | 37.5 | 0.375 mL |
| Weeks 13-16 | 10 mg | 50 | 0.500 mL |
| Weeks 17-20 | 12.5 mg | 62.5 | 0.625 mL |
| Week 21+ | 15 mg | 75 | 0.750 mL |
Tirzepatide has an elimination half-life of approximately 5 days, which supports once-weekly dosing.
Add your chosen volume of bacteriostatic water to the lyophilized vial, directing the stream against the glass wall, and swirl gently (do not shake) until fully dissolved. The calculator converts your vial strength and water volume into the units to draw for your target dose.
It depends on your concentration. With a 30 mg vial in 3 mL of water (10 mg/mL), 2.5 mg is 0.25 mL, or 25 units on a U-100 syringe. Enter your own vial and water amounts above to get your number.
Source: FDA Mounjaro (tirzepatide) Prescribing Information · How we calculate