Tirzepatide 50 mg reconstituted with 4 mL

Concentration

12.5mg/mL

Per insulin unit
125 mcg
Solution in vial
400 u
12.5 mg draw
100 u

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

Units per dose at 12.5 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 mg0.2 mL20 uU-3020
5 mg0.4 mL40 uU-5010
7.5 mg0.6 mL60 uU-1006
10 mg0.8 mL80 uU-1005
12.5 mg1 mL100 uU-1004
15 mg1.2 mL120 usplit draw3

Amber rows exceed 100 units — more than one full U-100 barrel. That dose needs a larger draw or a stronger mix (less water).

How this is calculated

  1. 1 · Concentration

    50 mg ÷ 4 mL = 12.5 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 12.5 mg dose

    12.5 mg ÷ 12.5 mg/mL = 1 mL

  3. 3 · Insulin units

    1 mL × 100 = 100 units

    Every unit on the barrel carries 125 mcg at this concentration, so misreading by one unit is a 125 mcg error.

See it on a real syringe

The interactive calculator draws this 12.5 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 50 mg Tirzepatide vial?
Adding 4 mL of bacteriostatic water to a 50 mg Tirzepatide vial yields 12.5 mg/mL — 125 mcg in every insulin unit. The reconstituted vial holds 400 units of solution in total.
How many units is a 12.5 mg dose of Tirzepatide at 50 mg in 4 mL?
12.5 mg is 1 mL of this mix, which is 100 units on a U-100 insulin syringe (a U-100 barrel is enough).
How many 12.5 mg doses does a 50 mg vial give?
A 50 mg vial contains 4 full 12.5 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 →