Reconstitution calculator

How the calculation works

Reconstitution does not change how much peptide is in the vial. It only sets the concentration. Three steps:

1. Concentration = peptide in vial ÷ water added. A 5 mg vial with 2 mL of water is 2.5 mg/mL, which is 2,500 mcg/mL.
2. Volume per dose = target dose ÷ concentration. A 250 mcg dose ÷ 2,500 mcg/mL = 0.1 mL.
3. Syringe units = volume × 100 on a U-100 insulin syringe. 0.1 mL = 10 units.

"Units" on an insulin syringe are a volume, not an amount of drug. Ten units of one vial and ten units of another can be completely different doses. Always work from mcg or mg and let the syringe units fall out of the math.

Picking a water volume

Aim for a dose that lands between about 5 and 50 units. Under 5 units is hard to read accurately on the syringe. Over 50 units means big injections and, for small vials, wasted product in the syringe dead space. If your dose comes out to 2 units, add more water. If it comes out to 80 units, add less next time.