Tirzepatide dosage calculator
Calculate the concentration and insulin-syringe units for a reconstituted tirzepatide vial. Enter the peptide amount in the vial, the bacteriostatic water you add, and your dose.
These values are an editable example to show how the calculator works — not a dosing recommendation. Enter your own vial size, water, and dose.
Tirzepatide is a dual GIP and GLP-1 receptor agonist. The FDA-approved products arrive pre-mixed and ready to use, so reconstitution maths only applies to lyophilised vials that ship as a powder and have to be dissolved before any volume can be drawn.
Reconstitution never changes how much drug is in a dose — it changes the volume that dose occupies, and therefore the number of units you draw. Add more bacteriostatic water for a weaker, easier-to-read solution, or less for a concentrated one; the calculator converts either into exact U-100 syringe units.
Common Tirzepatide vial sizes are 5 mg, 10 mg, 15 mg, 30 mg.
Tirzepatide is FDA-approved as the branded products Mounjaro (type 2 diabetes) and Zepbound (obesity), which come as pre-filled pens or vials. This calculator is a general reconstitution aid, not guidance for any specific product, and is not medical advice.
How to reconstitute Tirzepatide
- 1Let both the peptide vial and the bacteriostatic water reach room temperature, and wipe each rubber stopper with an alcohol swab.
- 2Draw the amount of bacteriostatic water you entered above into a syringe.
- 3Add the water slowly, aiming the stream down the inside glass wall of the Tirzepatide vial rather than directly onto the powder.
- 4Let the powder dissolve on its own; swirl gently if needed. Do not shake.
- 5Once the solution is clear, read the “draw to” figure above and draw that many units on a U-100 insulin syringe.
- 6Store the reconstituted vial as directed by your supplier — usually refrigerated — and note the date.