Tools

Reconstitution and syringe-unit calculator

Vial strength and solvent volume in; concentration, dose volume and syringe units out, with the arithmetic shown.

Three numbers go in — how much peptide is in the vial, how much solvent you add, and the dose you want. Everything else is arithmetic.

The distinction that causes the most errors on this site is between volume and units. A U-100 insulin syringe is marked in units where 100 units is 1 mL, so a unit is a volume in disguise. It is not a dose, and it means nothing until you know the concentration.

Peptide in vial (mg)as printed on the vial

Solvent added (mL)bacteriostatic water

Dose wanted

Dose unit1 mg = 1000 mcg

Syringe

—Draw to this mark

—Concentration

—Volume per dose

—Doses per vial

Notes

Adding solvent does not change how much peptide is in the vial. A 5 mg vial contains 5 mg whether you add 1 mL or 3 mL — you are choosing how dilute it is, and therefore how large and how measurable each dose is.

Bacteriostatic water contains a preservative and is what you want for a vial used over weeks; sterile water has none. Add the solvent slowly down the vial wall and swirl rather than shake — peptides are proteins and agitation denatures them. If it foams, that was too rough.

Maintained by the wiki editors. It runs entirely in your browser — nothing is sent anywhere — and it shows its working so you can check it by hand. Do it by hand the first few times. Nothing here is medical advice; see the disclaimer.

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