Guide: Mixing Peptides with Bacteriostatic Water

Peptide Reconstitution Guide

Peptide reconstitution is the process of adding bacteriostatic water to a dry peptide powder so it becomes a liquid solution that can be measured with a syringe.

Many research peptides come as a lyophilized powder, which means they are dry and must be mixed before they can be measured in syringe units.

Most peptide vials are labeled in mg, while many dosing discussions use mcg and syringe units. That is why reconstitution math can feel confusing at first.

Simple idea:
The peptide amount stays the same. The water amount only changes how concentrated each syringe unit becomes.

What Reconstitution Means

Before mixing

The vial contains dry peptide powder.

After mixing

Bacteriostatic water is added, creating a liquid solution that can be measured.

Why it matters

The amount of water added determines how many syringe units equal a specific dose.

Basic Reconstitution Formula

The concentration of a peptide solution depends on two things:

• The amount of peptide in the vial
• The amount of bacteriostatic water added

Vial strength ÷ water added = concentration

Basic Conversions

• 1 mg = 1,000 mcg
• 1 mL = 100 units on a standard U-100 insulin syringe
• 5 mg = 5,000 mcg
• 10 mg = 10,000 mcg
• 15 mg = 15,000 mcg

Example: 10mg Vial + 2mL Water

A common example is a 10mg vial mixed with 2mL bacteriostatic water.

Step-by-step math

• 10mg = 10,000mcg
• 2mL = 200 units
• 10,000mcg ÷ 200 units = 50mcg per unit

In this example, every 1 syringe unit contains about 50mcg.

Common Reconstitution Example

Using a 10mg vial mixed with 2mL bacteriostatic water:

Dose	Syringe Units
100mcg	2 units
250mcg	5 units
500mcg	10 units
1mg	20 units

How to Reconstitute a Peptide

Step 1

Clean the vial stopper with an alcohol pad.

Step 2

Draw the selected amount of bacteriostatic water into a syringe.

Step 3

Slowly inject the water into the vial, aiming it toward the side of the glass instead of directly blasting the powder.

Step 4

Let the liquid run down the side of the vial.

Step 5

Gently swirl or roll the vial until dissolved. Do not shake aggressively.

Simple rule:
Be gentle. Peptides can be delicate, and rough shaking may reduce stability.

What Not to Do

Do not shake hard

Gentle swirling is usually preferred because peptides can be fragile.

Do not assume all vials are the same

A 5mg vial and 10mg vial may look identical, but the concentration is different.

Do not ignore water volume

Adding more water does not add more peptide. It only makes the solution less concentrated.

Shelf Life After Reconstitution

Once a peptide is mixed, it does not last forever.

• Most reconstituted peptides are generally used within 14–30 days
• They should usually be stored refrigerated
• Heat, light, and time can reduce stability
• Potency can decrease even if the solution still looks clear

Beginner mistake:
“If it looks fine, it must still be good.” That is not always true.

Use the Peptide Calculator

For exact calculations based on your vial size, water amount, and target dose, use the interactive calculator.

Open the Peptide Dosage Calculator →

Peptide Research Tools

• Peptide Dosage Calculator
• Peptide Protocol & Calculator
• Peptide Mixing Chart
• Peptide Reconstitution Guide

Peptide Specific Calculators

• BPC-157 Dosage Calculator
• TB-500 Dosage Calculator
• GHK-Cu Dosage Calculator
• CJC-1295 Dosage Calculator
• Semax Dosage Calculator

Disclaimer: This information is provided for educational and research discussion purposes only and does not constitute medical advice.