Retatrutide 40 mg reconstituted with 5 mL

Concentration

8mg/mL

Per insulin unit
80 mcg
Solution in vial
500 u
8 mg draw
100 u

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

Units per dose at 8 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
1 mg0.125 mL12.5 uU-3040
2 mg0.25 mL25 uU-3020
4 mg0.5 mL50 uU-5010
6 mg0.75 mL75 uU-1006
8 mg1 mL100 uU-1005

How this is calculated

  1. 1 · Concentration

    40 mg ÷ 5 mL = 8 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 8 mg dose

    8 mg ÷ 8 mg/mL = 1 mL

  3. 3 · Insulin units

    1 mL × 100 = 100 units

    Every unit on the barrel carries 80 mcg at this concentration, so misreading by one unit is a 80 mcg error.

See it on a real syringe

The interactive calculator draws this 8 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 Retatrutide vial?
Adding 5 mL of bacteriostatic water to a 40 mg Retatrutide vial yields 8 mg/mL — 80 mcg in every insulin unit. The reconstituted vial holds 500 units of solution in total.
How many units is a 8 mg dose of Retatrutide at 40 mg in 5 mL?
8 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 8 mg doses does a 40 mg vial give?
A 40 mg vial contains 5 full 8 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 →