Retatrutide 40 mg reconstituted with 1 mL

Concentration

40mg/mL

Per insulin unit
400 mcg
Solution in vial
100 u
8 mg draw
20 u

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

Units per dose at 40 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 mg0.025 mL2.5 uU-3040
2 mg0.05 mL5 uU-3020
4 mg0.1 mL10 uU-3010
6 mg0.15 mL15 uU-306
8 mg0.2 mL20 uU-305

How this is calculated

  1. 1 · Concentration

    40 mg ÷ 1 mL = 40 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 ÷ 40 mg/mL = 0.2 mL

  3. 3 · Insulin units

    0.2 mL × 100 = 20 units

    Every unit on the barrel carries 400 mcg at this concentration, so misreading by one unit is a 400 mcg error.

See it on a real syringe

The interactive calculator draws this 40 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 1 mL of bacteriostatic water to a 40 mg Retatrutide vial yields 40 mg/mL — 400 mcg in every insulin unit. The reconstituted vial holds 100 units of solution in total.
How many units is a 8 mg dose of Retatrutide at 40 mg in 1 mL?
8 mg is 0.2 mL of this mix, which is 20 units on a U-100 insulin syringe (a U-30 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 →