Why Reconstitution Matters
Research peptides are shipped as lyophilised (freeze-dried) powder because the dry form is stable at room temperature for months. Once reconstituted into solution, peptides are far more delicate — degrading faster, especially if handled incorrectly. Getting reconstitution right preserves potency and ensures accurate dosing.
What You Need
- Bacteriostatic Water (BW) — sterile water containing 0.9% benzyl alcohol, which prevents bacterial growth in the vial after reconstitution. This is the standard diluent for peptides.
- Insulin syringes — 1 mL, 100-unit insulin syringes for both reconstitution and injection. The "IU" markings are a volume measure (1 IU = 0.01 mL).
- Alcohol swabs — for sterilising vial tops before each draw.
- A refrigerator — reconstituted peptides must be stored at 2–8°C (refrigerator temperature).
Step-by-Step Reconstitution
- Calculate your diluent volume. A common approach: add 1 mL of bacteriostatic water to a 5 mg vial. This gives a concentration of 5 mg/mL, or 5000 mcg/mL.
- Swab both vials. Wipe the top of the peptide vial and the BW vial with an alcohol swab. Wait for it to dry.
- Draw the bacteriostatic water. Using an insulin syringe, draw the desired volume of BW (e.g., 100 IU = 1 mL).
- Inject slowly into the peptide vial. Point the needle at the glass wall of the vial (not directly onto the powder). Let the water run down the side slowly.
- Do not shake. Gently swirl or roll the vial between your palms until the powder dissolves completely. Shaking can denature some peptides.
- Label the vial with the peptide name, concentration, reconstitution date, and expiry (typically 30–60 days refrigerated).
Calculating Your Dose
Example: You have a 5 mg vial of BPC-157, reconstituted with 1 mL of bacteriostatic water.
- Concentration = 5000 mcg / 1 mL = 5000 mcg/mL
- Desired dose = 250 mcg
- Volume to draw = 250 mcg ÷ 5000 mcg/mL = 0.05 mL = 5 IU on an insulin syringe
Peptalytix handles this calculation automatically — enter your vial size and bacteriostatic water volume when logging a vial, and the app will show you exactly how many IU to draw for any dose.
Storage
- Lyophilised (unreconstituted): Store at room temperature, away from light and heat. Stable for 12–24 months. Can be stored in the freezer for extended shelf life.
- Reconstituted: Refrigerate immediately at 2–8°C. Use within 30–60 days depending on the peptide. Some peptides (e.g., GHRPs) are more fragile and should be used within 30 days.
- Never freeze reconstituted peptides — the freeze-thaw cycle degrades the solution. If you need long-term storage, keep them lyophilised.
Injection Technique
Subcutaneous (SC): The most common route. Pinch a fold of skin (abdomen, thigh, or lower back fat) and insert the needle at 45°. Release the skin fold before injecting slowly. SC injections result in gradual absorption.
Intramuscular (IM): Faster absorption. Common sites: deltoid, vastus lateralis (outer thigh), or glute. Insert at 90° directly into the muscle. Not necessary for most peptides but preferred for some (e.g., local BPC-157 near a muscle injury).
Common Mistakes to Avoid
- Shaking the vial vigorously — always swirl gently
- Using regular sterile water instead of bacteriostatic water (causes rapid bacterial contamination)
- Leaving reconstituted peptides at room temperature for hours before injection
- Reusing needles — always use a fresh needle for each injection
- Injecting into scar tissue — rotate injection sites