Tirzepatide is a dual GIP and GLP-1 receptor agonist. It is the active ingredient in Mounjaro and Zepbound, both once-weekly injections.
Also known as: Mounjaro, Zepbound.
Mounjaro and Zepbound pens, and Zepbound single-dose vials, are already in solution and need no mixing. Powder vials of tirzepatide are usually labeled 5 mg, 10 mg, 15 mg, 20 mg or 30 mg.
Here is the math for a 10 mg vial mixed with 2 mL of bacteriostatic water, drawing 2.5 mg with a U-100 insulin syringe (1 mL = 100 units).
10 mg ÷ 2 mL = 5 mg/mL2.5 mg ÷ 5 mg/mL = 0.5 mL0.5 mL × 100 = 50 units| Amount | Volume | U-100 syringe |
|---|---|---|
| 1.25 mg | 0.25 mL | 25 units |
| 2.5 mg | 0.5 mL | 50 units |
| 5 mg | 1 mL | 100 units |
Adding more water doesn't change how much tirzepatide is in the vial. It only spreads it over more liquid, so each draw is bigger and easier to read.
| Water added | Concentration | Volume | U-100 syringe |
|---|---|---|---|
| 1 mL | 10 mg/mL | 0.25 mL | 25 units |
| 2 mL | 5 mg/mL | 0.5 mL | 50 units |
| 3 mL | 3.33 mg/mL | 0.75 mL | 75 units |
For any other vial size or amount, the free peptide reconstitution calculator works backwards from the amount you want and suggests a water volume that lands on a clean syringe mark.
The FDA Mounjaro label gives an elimination half-life of about 5 days and a time to peak of 8 to 72 hours after an injection.
Numbers shown are the values Dose Track uses, listed only where they agree with the source above. Half-life varies from person to person and with injection site.