# How to Reconstitute Peptides: A Complete Beginner's Guide
If you're new to peptides, reconstitution is the step that trips people up most. The vials you receive contain a lyophilized (freeze-dried) powder — you need to add liquid to activate it before injecting. This guide covers everything you need to know, including the exact math to calculate your dose.
What You Need
Before you start, have these supplies ready:
- Bacteriostatic water (BAC water) — sterile water with 0.9% benzyl alcohol. This is not the same as saline or plain sterile water. The benzyl alcohol preserves your peptide in solution for 4-6 weeks in the fridge.
- Insulin syringes — 29-31 gauge, 0.5" needle, 1mL capacity with 100-unit markings. These are available on Amazon or at pharmacies without a prescription.
- Alcohol swabs — wipe every vial top before drawing from it.
- Concentration (mg/mL) = Peptide amount (mg) ÷ BAC water volume (mL)
- Units per dose = Dose (mg) ÷ Concentration (mg/mL) × 100
- Wipe the top of the BAC water vial with an alcohol swab
- Draw the desired amount of BAC water into your syringe (e.g., 2mL = 200 units on a 100-unit syringe)
- For larger volumes, you may need to draw in two pulls with the same syringe
- Wipe the top of your peptide vial with an alcohol swab
- Insert the needle and slowly inject the BAC water down the side of the vial — do not shoot it directly onto the powder
- Let it sit for 60-90 seconds. Gently swirl (never shake). The powder should dissolve into a clear solution.
- Store in the refrigerator (not freezer)
- Keep away from light
- Most peptides remain stable for 4-6 weeks when stored properly with BAC water
- Use a fresh alcohol swab to clean the stopper every time you draw from it
- Wipe the stopper with an alcohol swab
- Draw slightly more than your dose volume, then expel air bubbles and excess to the exact amount
- For 10 units on a 100-unit syringe: fill to the "10" mark
- Inject subcutaneously (subQ) — pinch a fold of skin at the injection site, insert at a 45-degree angle, inject slowly, remove and press gently with a clean swab
Where to get BAC water: Amazon ("bacteriostatic water for injection" in 30mL vials), most pharmacies, or American Peptide Research. One 30mL vial will last you months since you only use 1-2mL per peptide vial.
The Reconstitution Process
Step 1: Gather Your Supplies
Wash your hands thoroughly. Work on a clean surface. Have your peptide vial, BAC water vial, and syringe ready.
Step 2: Decide How Much BAC Water to Add
This is where beginners get confused, but the math is straightforward. The amount of BAC water you add determines your concentration — which determines how many units you draw for each dose.
The formula:
Common examples:
| Peptide | Vial Size | BAC Water | Concentration | Dose | Units to Draw |
| TB-500 | 10mg | 2mL | 5mg/mL | 0.5mg/day | 10 units |
| BPC-157 | 5mg | 2.5mL | 2mg/mL | 250mcg (0.25mg) | 12.5 units |
| GHK-Cu | 50mg | 5mL | 10mg/mL | 1mg/day | 10 units |
| BPC-157 | 5mg | 1mL | 5mg/mL | 250mcg (0.25mg) | 5 units |
You can use any BAC water volume that gives you easy-to-draw amounts. More water = easier to measure small doses. Less water = fewer injections per vial.
Use the PeptIQ reconstitution calculator to get the exact math for your specific vial and dose in seconds.
Step 3: Draw the BAC Water
Step 4: Add BAC Water to the Peptide Vial
If your solution is cloudy or has particles that don't dissolve, do not use it.
Step 5: Store It Correctly
Once reconstituted:
Drawing Your Dose
Using the concentrations from the table above:
Frequently Asked Questions
Q: Can I use saline instead of bacteriostatic water?
A: No. Regular saline doesn't contain the preservative that keeps peptides stable. Your reconstituted peptide will degrade much faster and risk bacterial contamination. Always use BAC water.
Q: Can I mix two peptides in the same vial?
A: No. Reconstitute each peptide separately. Mixing peptides in the same vial risks pH changes that degrade both compounds. Draw them from separate vials and inject in the same area if you want.
Q: How long does a reconstituted peptide last?
A: With bacteriostatic water, properly refrigerated: 4-6 weeks for most peptides. Keep a note of the date you reconstituted it.
Q: What if I use too much or too little BAC water?
A: It affects your concentration but not the effectiveness of the peptide — you just adjust how many units you draw. More BAC water = draw more units per dose. Less BAC water = draw fewer units. The math stays the same.
Q: My solution looks cloudy — is that okay?
A: Most peptides should dissolve into a clear solution. Persistent cloudiness can indicate degradation or contamination. When in doubt, don't use it.
Q: What gauge needle for injections?
A: 29-31 gauge, 0.5" length is standard for subQ peptide injections. 29g 1/2" insulin syringes are widely available on Amazon without a prescription.
Track Your Protocol with PeptIQ
Once you have your reconstitution dialed in, the next challenge is consistency. PeptIQ helps you log every dose, track reconstitution dates, set injection reminders, and monitor your results over time — so you stay on protocol and can actually see what's working.
Download PeptIQ to manage your full peptide protocol in one place.