Peptide reconstitution & dosage guide

Peptide reconstitution means mixing freeze-dried peptide powder with bacteriostatic water so it becomes a liquid you can draw into a syringe. The amount of water you add changes the concentration, which is why dose calculations matter.

A common starting point is 2 mL of BAC water per 5 mg of peptide. This gives 2.5 mg/mL, or 2500 mcg/mL. Add 1 mL for a stronger 5 mg/mL mix, or 3 mL for a gentler 1.67 mg/mL mix. Use the calculator above to try any volume and see the exact units to draw.

2 mL of BAC water in a 10 mg vial gives 5 mg/mL (5000 mcg/mL). A 250 mcg dose is 0.05 mL, or 5 units on a U-100 insulin syringe. Many people use 2 mL for BPC-157, TB-500 and Ipamorelin 10 mg vials because the math is clean.

Find your concentration in mg/mL, divide your target dose by that concentration to get mL, then multiply by 100 for a U-100 insulin syringe (or by 40 for a U-40 syringe). Example: 0.25 mg ÷ 2.5 mg/mL = 0.1 mL = 10 units on U-100.

Divide the total vial milligrams by your dose in milligrams. A 5 mg vial at 0.25 mg per dose gives 20 doses. A 10 mg vial at the same dose gives 40 doses. The calculator above shows this automatically.

Semaglutide is dosed in milligrams but drawn in units. If a 5 mg vial is reconstituted with 2 mL of BAC water, that is 2.5 mg/mL. A 0.25 mg starting dose = 0.1 mL = 10 units on a U-100 insulin syringe. A 0.5 mg dose = 20 units. A 1 mg dose = 40 units.

For a 10 mg tirzepatide vial reconstituted with 2 mL of BAC water (5 mg/mL): a 2.5 mg starting dose = 0.5 mL = 50 units on a U-100 insulin syringe. A 5 mg dose = 100 units (a full 1 mL insulin syringe). Many users split into two smaller draws for higher doses.

Common research-cited BPC-157 doses range from 200 to 500 mcg per day. With a 5 mg vial reconstituted in 2 mL of BAC water (2.5 mg/mL), 250 mcg = 0.1 mL = 10 units on a U-100 syringe. Always follow guidance from a licensed clinician.

Research protocols commonly cite 2–2.5 mg of TB-500 twice weekly during a loading phase, then a maintenance dose. A 5 mg vial in 2 mL BAC water (2.5 mg/mL) means 2.5 mg = 1 mL = 100 units on a U-100 syringe.

Typical Ipamorelin protocols use 200–300 mcg per injection, 1–3 times daily. With a 5 mg vial in 2 mL of BAC water (2.5 mg/mL), 300 mcg = 0.12 mL = 12 units on a U-100 insulin syringe.

A U-100 syringe has 100 units per mL. A U-40 syringe has 40 units per mL. If you use a U-40 syringe with a U-100 concentration you will under-dose by 60%. Always confirm which syringe you have — the calculator above supports both.

Once mixed with bacteriostatic water, most peptides are considered stable for roughly 28 days refrigerated at 2–8°C (36–46°F). Sensitive peptides like GLP-1s and BPC-157 are often used within 30 days. Keep vials upright, protected from light, and never freeze after reconstitution unless the manufacturer specifies it.

Sterile water has no preservative, so a reconstituted vial should be used within 24 hours. Bacteriostatic water contains 0.9% benzyl alcohol which inhibits bacterial growth and extends usable life to roughly 28 days refrigerated. Bacteriostatic water is the standard choice for multi-dose peptide vials.

A peptide reconstitution calculator converts a target dose in milligrams or micrograms into the exact volume to draw on an insulin syringe, based on how much bacteriostatic water you added to the vial. It also shows the resulting concentration in mg/mL and how many doses the vial contains.

No. The reconstitution and dose calculator on this page runs entirely in your browser and requires no sign-up. Enter the vial strength, BAC water volume and target dose to get the syringe units instantly.

To keep a record of each injection, most people use a dose-tracking app that supports vial inventory, injection site rotation and reminder alarms. That way the calculator handles the math and the tracker handles the schedule and history.