Tirzepatide 40 mg reconstituted with 1.5 mL

Concentration

26.67mg/mL

Per insulin unit
266.7 mcg
Solution in vial
150 u
15 mg draw
56.3 u

Math utility only — not medical advice. Not a recommended dose.

Units per dose at 26.67 mg/mL

Insulin syringes are graduated in hundredths of a millilitre, so units = mL × 100 on a U-100, U-50 or U-30 barrel alike.

DoseVolumeU-100 unitsFitsDoses per vial
2.5 mg0.094 mL9.4 uU-3016
5 mg0.188 mL18.8 uU-308
7.5 mg0.281 mL28.1 uU-305
10 mg0.375 mL37.5 uU-504
12.5 mg0.469 mL46.9 uU-503
15 mg0.563 mL56.3 uU-1002

How this is calculated

  1. 1 · Concentration

    40 mg ÷ 1.5 mL = 26.67 mg/mL

    The peptide mass never changes — bacteriostatic water only sets how concentrated the solution is, and therefore how far the plunger travels.

  2. 2 · Volume for a 15 mg dose

    15 mg ÷ 26.67 mg/mL = 0.563 mL

  3. 3 · Insulin units

    0.563 mL × 100 = 56.3 units

    Every unit on the barrel carries 266.7 mcg at this concentration, so misreading by one unit is a 266.7 mcg error.

See it on a real syringe

The interactive calculator draws this 26.67 mg/mL mix on a scaled U-100 barrel, shows when a draw lands exactly on a printed tick, and works backwards from a target dose to the water volume that makes it land cleanly.

Open the interactive calculator →

Common questions

How much bacteriostatic water for a 40 mg Tirzepatide vial?
Adding 1.5 mL of bacteriostatic water to a 40 mg Tirzepatide vial yields 26.67 mg/mL — 266.7 mcg in every insulin unit. The reconstituted vial holds 150 units of solution in total.
How many units is a 15 mg dose of Tirzepatide at 40 mg in 1.5 mL?
15 mg is 0.563 mL of this mix, which is 56.3 units on a U-100 insulin syringe (a U-100 barrel is enough).
How many 15 mg doses does a 40 mg vial give?
A 40 mg vial contains 2 full 15 mg doses. Using more or less bacteriostatic water changes the units you draw, never the number of doses in the vial.
All 211 reconstitution combinations →