How to Reconstitute Peptides: Step-by-Step Guide

What you need

A lyophilized (freeze-dried) peptide vial, bacteriostatic water, an alcohol swab, and two syringes: a larger one (3 ml with a drawing needle) for adding water, and U-100 insulin syringes for dosing. All supplies should be sterile and single-use.

Step by step

1. Wash hands and swab both vial tops (peptide and water) with alcohol.

2. Draw your chosen amount of bacteriostatic water — typically 2–3 ml for a 5 mg vial. The exact amount only changes concentration; use our calculator to pick a number that gives convenient syringe units.

3. Inject the water into the peptide vial SLOWLY, aiming the stream at the glass wall — not directly onto the powder. Peptide molecules are fragile and a direct jet can damage them.

4. Do not shake. Gently swirl or roll the vial, or simply let it sit — most peptides dissolve fully within a few minutes.

5. Label the vial with the peptide name, concentration and date, then refrigerate.

Common mistakes

Shaking the vial (degrades the peptide), using plain sterile water for a multi-week vial (no preservative), forgetting to note how much water went in (makes every future dose a guess), and doing concentration math in your head at the moment of injection. Write it down once, or keep the calculator bookmarked.

After mixing: the math

Concentration = peptide mcg ÷ water ml. Dose volume = desired mcg ÷ concentration. Units on a U-100 syringe = volume ml × 100. Example: 5 mg vial + 2 ml water = 2,500 mcg/ml; a 250 mcg dose = 0.1 ml = 10 units.