How to Reconstitute Peptides: Complete Step-by-Step Guide

How to Reconstitute Peptides: Complete Step-by-Step Guide

Learn exactly how to reconstitute peptides with bacteriostatic water: step-by-step mixing instructions, reconstitution ratios for BPC-157, semaglutide, CJC-1295/Ipamorelin and more, plus storage tips.

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What You'll Need

Gather everything before you start so the vial isn't left open longer than necessary.

Bacteriostatic water

Sterile water with 0.9% benzyl alcohol — the standard diluent for peptide reconstitution. Do not substitute plain sterile water for long-term storage.

Peptide vial

Your lyophilized (freeze-dried) peptide, still sealed, stored at room temperature or refrigerated until use.

Syringe & alcohol swabs

An insulin syringe sized to the volume of water you're drawing, plus alcohol swabs to sanitize both vial tops.

Step 1: Sanitize Both Vial Tops

Wipe the rubber stopper of the peptide vial and the bacteriostatic water vial with a fresh alcohol swab.

Swab both stoppers

Use a new alcohol swab on the peptide vial and another on the bacteriostatic water vial to prevent contamination.

Let it air-dry

Wait a few seconds for the alcohol to evaporate before inserting a needle, which keeps alcohol out of the vial.

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Step 2: Draw Air Into the Syringe

Pull back the plunger to draw an amount of air equal to the amount of water you're about to add.

Match air to water volume

Drawing air first and injecting it into the water vial equalizes pressure, making the water easier to draw out cleanly.

Step 3: Draw the Bacteriostatic Water

Inject the air into the water vial, invert it, and draw out the exact amount of water your ratio calls for.

Use the calculator for exact volume

The amount of water you add determines your final concentration, so use the dosage calculator to keep your ratio precise.

Check for air bubbles

Tap the syringe and push out any trapped air before removing the needle from the vial.

Step 4: Inject the Water Slowly

Insert the needle through the peptide vial's stopper at an angle, aiming the stream down the inside glass wall.

Aim down the glass, not the powder

Letting the water run down the wall instead of blasting the lyophilized powder directly prevents the peptide from foaming or degrading.

Go slowly

A slow, steady injection over several seconds protects the peptide's structure far better than a quick push.

Step 5: Swirl, Never Shake

Gently roll or swirl the vial between your palms until the powder fully dissolves into a clear solution.

Do not shake the vial

Shaking introduces agitation that can denature the peptide's structure. Swirling is gentle enough to dissolve it without damage.

Confirm it's fully clear

The solution should look clear with no visible particles or cloudiness before you draw a dose.

Step 6: Label the Vial

Write the reconstitution date and final concentration directly on the vial or a piece of tape.

Note the date and concentration

Once mixed, it's easy to lose track of when a vial was reconstituted, so label it immediately to keep dosing accurate.

Peptide Reconstitution Ratio Chart: BPC-157, TB-500, CJC-1295 & More

A quick-reference table for how much bacteriostatic water to add per vial, plus typical dosing, frequency, and cycle length for the most commonly researched peptides. Tap any peptide for its full reconstitution guide. Always confirm the ratio against your own vial's exact mg amount before drawing a dose. For research purposes only, not for human consumption or therapeutic use.

BPC

Healing

Tb5

CjCi

Growth

PT-141

Sexual

Ser

Aod

Weight

Common Reconstitution Mistakes to Avoid

Most reconstitution problems come down to one of these three errors.

Shaking instead of swirling

Vigorous shaking is the most common cause of a degraded peptide solution. Always swirl gently.

Using the wrong diluent

Plain sterile water lacks the preservative that keeps a reconstituted vial stable for weeks, use bacteriostatic water.

Skipping the calculator

Eyeballing the water volume leads to inconsistent, inaccurate dosing. Always calculate the exact ratio first.

How to Store a Reconstituted Vial

Proper storage is what determines how long your reconstituted peptide stays stable.

Refrigerate immediately

Store the vial at 36–46°F (2–8°C), away from light, as soon as it's mixed.

Use within the labeled window

Most reconstituted peptides remain stable for roughly 2–4 weeks refrigerated, check your specific peptide's guidance.

Keep it out of direct light

UV exposure accelerates degradation, store the vial in its original box or a dark drawer inside the fridge.

Reconstitution Questions, Answered

The most common questions people have before mixing their first vial.

How much bacteriostatic water do I use per mg of peptide?

It depends on your target concentration, not a fixed rule — most 5mg vials use 1–2mL of bacteriostatic water, which gives a workable concentration for standard insulin syringes. Use a reconstitution calculator to match the water volume to your specific vial and desired dose.

Can I use sterile water instead of bacteriostatic water?

You can, but the vial must be used the same day and cannot be stored — sterile water has no preservative. Bacteriostatic water contains 0.9% benzyl alcohol, which keeps the solution stable for weeks under refrigeration.

Why shouldn't I shake the vial?

Shaking creates agitation and foaming that can break down the peptide's molecular structure. Gently swirling or rolling the vial between your palms dissolves the powder without that risk.

How long do peptides last after reconstitution?

Most reconstituted peptides remain stable for about 2–4 weeks when refrigerated at 36–46°F (2–8°C). Some peptides are more or less stable than others, so always check the specific guidance for the peptide you're using.

Do reconstituted peptides need to be refrigerated?

Yes. Refrigeration significantly slows degradation. Leaving a reconstituted vial at room temperature for extended periods shortens its usable life considerably.

What happens if I add too much or too little water?

Adding too much water dilutes the peptide, so each syringe draw contains less active compound than intended. Adding too little makes the solution overly concentrated, which can make precise low-dose measurements harder. In both cases, your calculated dosing will be off.

Can I reconstitute peptides at room temperature?

Yes, mixing itself can be done at room temperature — the peptide only needs to be refrigerated after it's reconstituted, not during the process.