How much Bacteriostatic water do I add to reconstitute my peptide

How Much Bacteriostatic Water to Add to Peptides?

How Much Bacteriostatic Water Should I Use to Reconstitute My Peptide?


Peptides are becoming increasingly popular due to their cost-effective benefits and wide range of uses. However, one common question that arises is, "How much bacteriostatic water should I use to reconstitute my peptide?" The answer varies depending on your dosage needs. This article aims to guide you through the process of determining the correct amount of bacteriostatic water to use for your peptide, ensuring you achieve the ideal concentration for easy and accurate dosing.


Infographic Bac Water Peptides Reconstitute



Peptide Reconstitution Chart

This is for entertainment purposes only and does not constitute medical advise


Peptide Name 5mg Vial 10mg Vial

2ml bacteriostatic water
10 units = 0.25mg

2ml bacteriostatic water
5 units = 0.25mg

1ml bacteriostatic water
50 units = 2.5mg

1ml bacteriostatic water
25 units = 2.5mg
CJC 1295/Ipamorelin

1ml bacteriostatic water
5 units = 0.25mg

BPC 157

1ml bacteriostatic water
10 units = 0.5mg

1ml bacteriostatic water
5 units = 0.5mg
TB 500

1ml bacteriostatic water
10 units = 1mg

1ml bacteriostatic water
10 units = 1mg
PT 141


2ml bacteriostatic water
10 units = 1mg

(100mg vial)
3ml bacteriostatic water
3 units = 1mg

Melanotan 2 N/A

2ml bacteriostatic water
5 units = 0.25mg


1ml bacteriostatic water
50 units = 5mg

Epithalon N/A

1ml bacteriostatic water
10 units = 1mg


2.5ml bacteriostatic water
10 units = 200mcg

Semax N/A

2ml bacteriostatic water
10 units = 500mcg


2.5ml bacteriostatic water
5 units = 100mcg


Understanding Reconstitution: The Basics

Lyophilized peptides are freeze-dried and need to be reconstituted with bacteriostatic water before use. Bacteriostatic water is preferred because it contains a small amount of benzyl alcohol, which helps prevent bacterial growth, making it safe for multiple uses over an extended period. Proper reconstitution is crucial to ensure the peptide's effectiveness and to avoid potential issues with dosage accuracy.

Analogy: Espresso vs. Cafe Americano

To better understand the concept of reconstitution, let's use a simple analogy: espresso versus Cafe Americano. If you’ve ever been to a coffee shop, you know that an espresso shot is a small, concentrated dose of caffeine, while a Cafe Americano is an espresso shot diluted with hot water. Both drinks contain the same amount of caffeine, but the difference lies in the volume of water added.

Similarly, when reconstituting peptides, the amount of bacteriostatic water you use doesn’t change the total amount of peptide; it only affects the concentration. For lower dosages, you'll need more water to ensure the dose is easily measurable, while for higher dosages, you'll use less water to fit the dose into the syringe.

How Much Water to Add Video:

Factors Affecting Water Quantity

When determining how much water to use for reconstituting your peptide, consider the following factors:

  1. Dosage Requirements: Peptide dosages can vary significantly. Some require microgram (mcg) dosages, which are very small, while others require milligram (mg) dosages, which are larger.
  2. Syringe Capacity Constraints: Insulin syringes, commonly used for peptide injections, typically hold a maximum of 0.5 to 1.0 milliliters (mL). Therefore, the concentration of your reconstituted peptide should ensure that the entire dose can fit within the syringe without being too small to measure accurately.

Why You Don’t Want to Use Too Much or Too Little Water to Reconstitute Your Peptide

When reconstituting peptides, it's essential to use the correct amount of bacteriostatic water. Using too much or too little water can lead to problems that affect both the accuracy of your dosage and the overall effectiveness of your peptide therapy. Here’s why it's important to get the amount just right:

Problems with Using Too Much Water

  1. Inaccurate Dosing: When you use too much water, the concentration of the peptide in the solution becomes too diluted. This means that to get your required dose, you might need to draw a very large volume of the solution. For example, if you need a high dose but have added too much water, you may end up with a dose that exceeds the capacity of your syringe, making it impossible to measure and inject the correct amount accurately.
  2. Inconvenience: Larger volumes can be cumbersome and impractical. If you end up needing to inject a large volume of liquid, it can be uncomfortable and may require multiple injections, which is not ideal for most users.

Problems with Using Too Little Water

  1. Difficulty in Measuring: On the flip side, using too little water makes the peptide concentration very high. This can result in doses that are too small to measure accurately with a standard syringe. For instance, if your required dose is in micrograms (mcg) and you’ve used too little water, you may need to measure fractions of a milliliter, which can be challenging and imprecise.
  2. Risk of Overdosing: High concentrations increase the risk of overdosing. If you miscalculate or accidentally draw a bit more than intended, you could end up taking a much higher dose than required, which can lead to adverse effects or reduce the peptide's benefits.
  3. Injection Site Issues: Highly concentrated solutions can cause irritation at the injection site. If the peptide solution is too concentrated, it can be more likely to cause pain or inflammation when injected.

Finding the Balance

The key to successful peptide reconstitution lies in finding the right balance. You want to add enough bacteriostatic water to ensure that your dose fits comfortably within the syringe and can be measured accurately, but not so much that the solution becomes overly diluted and inconvenient to use.

For most peptides, aiming for a concentration that allows your dose to fall within the range of 5 to 50 units on an insulin syringe for your dose is ideal. This range ensures that your dose is neither too small to measure accurately nor too large to fit into the syringe.

By carefully calculating the amount of water to use based on your dosage needs, you can ensure that your peptide therapy is both effective and easy to manage. Always remember to follow the guidelines and use tools like the peptide calculator provided by Prime Peptides to help you achieve the perfect concentration for your needs.

Calculating the Correct Amount of Water

Calculating the right amount of water for your peptide involves a simple formula:

To calculate how many mg of peptide you have per mL after adding water, you simply divide the amount of peptide in the vial (mg) by the amount of water that you add (mL).

Let's break down this calculation with examples for both microgram and milligram dosages:

Dosages in Milligrams (mg) If you have a 10mg vial of peptide and add 2mL of water, the concentration will be 5mg/mL. This means each mL of the solution contains 5mg of the peptide.

      For example, if your required dose is 10mg per injection, you would use 1mL of the solution (10mg divided by 10mg/mL = 1mL).

      Dosages in Micrograms (mcg) Microgram dosages require more precise measurements. If you have a 5mg vial and add 5mL of water, the concentration will be 1mg/mL, which is equivalent to 1000mcg/mL (since 1mg = 1000mcg).

      For a dose of 125mcg, you would need to draw 0.125mL of the solution (125mcg divided by 1000mcg/mL = 0.125mL).

      Prime Peptides has a peptide calculator that you can use to determine the right calculations for your needed doses.

      Specific Examples

      To make things clearer, let’s go through specific examples for some common peptides:

      • Semaglutide: Available in 5mg or 10mg vials. For a 5mg vial, adding 5mL of water gives a 1mg/mL concentration. A starting dose of 0.25mg (250mcg) would require 0.25mL of this solution. For a 10mg vial, adding 1mL of water results in a 10mg/mL concentration, so a 2.4mg dose would need 0.24mL.
      • Tirzepatide: Comes in 5mg or 10mg vials. For a 5mg vial, adding 1mL of water gives a 5mg/mL concentration. A 2.5mg dose would need 0.5mL. For a 10mg vial, adding 2mL of water results in a 5mg/mL concentration, so a 5mg dose would require 1mL.
      • BPC-157: Typically available in 5mg or 10mg vials. For a 5mg vial, adding 5mL of water results in a 1mg/mL (1000mcg/mL) concentration. A 1000mcg dose would require 1mL of this solution. For a 10mg vial, adding 2.5mL of water gives a 4mg/mL (4000mcg/mL) concentration, so a 1000mcg dose would require 0.25mL.

      Peptide Reconstitution Cheat Sheet

      Here's a quick reference for some common peptides and their ideal reconstitution ratios:

      • Semaglutide: 5mg vial + 5mL water = 1mg/mL; 10mg vial + 1mL water = 10mg/mL
      • BPC-157: 5mg vial + 5mL water = 1mg/mL (1000mcg/mL); 10mg vial + 2.5mL water = 4mg/mL (4000mcg/mL)
      • Tirzepatide: 5mg vial + 1mL water = 5mg/mL; 10mg vial + 2mL water = 5mg/mL

      By following these guidelines and calculations, you can ensure that you reconstitute your peptides correctly, making your dosing accurate and efficient.

      Using the Peptide Calculator

      To simplify the reconstitution process, Prime Peptides offers a peptide calculator that helps you determine the correct calculations for your needed doses. By inputting the amount of peptide in the vial and the desired concentration, the calculator provides the precise amount of bacteriostatic water to add. This tool is especially useful for those who may find the math daunting or who want to double-check their calculations for accuracy.

      Common Mistakes to Avoid

      When reconstituting peptides, there are a few common mistakes that can affect the accuracy and effectiveness of your dosage:

      1. Over-dilution or Under-dilution: Adding too much or too little bacteriostatic water can lead to incorrect concentrations, making it difficult to measure the right dose. Always follow the calculations to ensure you add the correct amount of water.
      2. Improper Mixing: After adding the bacteriostatic water, gently swirl the vial to mix the solution. Avoid shaking the vial vigorously, as this can damage the peptide molecules.
      3. Storage Issues: Once reconstituted, peptides should be stored in the refrigerator to maintain their stability and potency. Always check the storage instructions provided with your peptide to ensure proper handling.

      Quick Reference Guide

      Here’s a summary of the key points to keep in mind:

      • Dosage Requirements: Know whether your peptide dosage is in micrograms (mcg) or milligrams (mg).
      • Syringe Capacity: Ensure the reconstituted peptide fits within the syringe's capacity (0.5 to 1.0 mL).
      • Calculation Formula: Use the formula: Concentration (mg/mL) = Amount of Peptide (mg) / Amount of Water (mL).
      • Peptide Calculator: Use Prime Peptides’ calculator for precise measurements.


        Reconstituting peptides correctly is crucial for ensuring accurate dosing and maximizing their benefits. By understanding the basics of reconstitution, using the espresso versus Cafe Americano analogy, and following the step-by-step calculations, you can easily determine the right amount of bacteriostatic water to use. Remember to utilize the peptide calculator for precise measurements and avoid common mistakes to achieve the best results.

        Peptides offer significant health and wellness benefits, and with the right knowledge and tools, you can make the most of your peptide therapy. Whether you're new to peptides or looking to refine your reconstitution technique, this guide provides the essential information you need for successful peptide use.

        By following these guidelines, you can ensure that your peptides are reconstituted correctly, making your dosing accurate and efficient. Happy peptide reconstitution!


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        3mg of semaglutide how much would I reconstitute for 20 units


        For 10mg Vial of tirzepatide how much would i reconstitute if I am on 100 units.? And how long will it last?

        Rosemarie Novinc

        How do I constitute a 10mg vial of tirzepatide?

        Anna Salinas

        I was told to mix only 1ML per 10mg of PT-141 and dose at 10mm is that correct?

        Joseph Malara

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