Reconstitution

Lyophilised (freeze-dried) peptide arrives as a white powder or fluffy disc at the bottom of a sealed glass vial. You add bacteriostatic water (BAC water) to turn it into an injectable solution.

What you need

• Peptide vial (kept cold since arrival)
• Bacteriostatic water — sterile water with 0.9% benzyl alcohol as preservative
• 3 ml syringe with 21g draw needle for BAC water
• Insulin syringes for dosing (0.5 ml, 29–31g)
• Alcohol swabs

Step by step

1. Let both vials come to room temperature (5–10 minutes on the counter).
2. Swab both rubber stoppers with alcohol and let them air-dry.
3. Draw your chosen volume of BAC water into the 3 ml syringe (see math below).
4. Insert the needle into the peptide vial at a 45° angle and slowly release the BAC water down the inside wall of the glass — do not squirt it directly onto the powder.
5. Remove the needle. Gently swirl (do not shake) until fully dissolved. Some peptides take 30 seconds; others sit for a few minutes.
6. Label the vial with peptide name, mg, ml of BAC, date. Store in the fridge (2–8 °C).

The dosing math

Concentration (mg/ml) = vial size in mg ÷ ml of BAC water added.

On a U-100 insulin syringe, 100 units = 1 ml. So 1 unit = 0.01 ml.

Units to draw for a dose = (desired dose in mg ÷ concentration in mg/ml) × 100.

Prefer to not do arithmetic? Use the calculator.

Storage & shelf life

• Lyophilised (unmixed) peptide: 2 years frozen, 2+ years refrigerated for most.
• Reconstituted with BAC water: 4–8 weeks refrigerated for most peptides.
• Reconstituted with sterile water (no preservative): 24 hours — not recommended.
• Never freeze reconstituted peptide — freeze/thaw cycles damage the peptide bonds.
• Keep out of direct light.

Common mistakes

• Shaking the vial — foams the solution and can denature the peptide.
• Squirting water directly onto the powder — same problem.
• Using sterile water instead of bacteriostatic water for multi-dose vials.
• Forgetting to label — after two weeks you will not remember the concentration.