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Reconstitution Cheat Sheet

Quick reference for mixing bacteriostatic water, calculating dosages, and proper storage. Print-friendly format with dosing tables.

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By Peptides.NYC Editorial TeamUpdated May 21, 2026

Educational content only. Not medical advice. The content creators are not doctors or medical professionals. Consult your healthcare provider before taking any action.

Quick Reference: Reconstitution Basics

Reconstitution is the process of adding bacteriostatic water (BAC water) to lyophilized (freeze-dried) peptide powder to create an injectable solution. This cheat sheet provides everything you need to reconstitute peptides safely and calculate accurate doses.


What You'll Need

Essential Supplies

  • Lyophilized peptide vial
  • Bacteriostatic water (BAC water with 0.9% benzyl alcohol)
  • Alcohol swabs
  • Insulin syringes (typically 1mL/100 unit or 0.5mL/50 unit)
  • Sharps container for needle disposal

Why Bacteriostatic Water?

BAC water contains benzyl alcohol, which prevents bacterial growth. This is essential for multi-use vials that you'll draw from over several weeks. Never use sterile water for multi-dose peptides—it has no preservative.


Step-by-Step Reconstitution

1. Prepare Your Workspace

  • Clean, flat surface
  • Good lighting
  • All supplies within reach
  • Hands washed or gloved

2. Check Your Vial

  • Verify peptide amount (usually printed on label: 5mg, 10mg, etc.)
  • Powder should appear intact (not melted or clumped)
  • Vial seal should be unbroken

3. Add Bacteriostatic Water

  1. Wipe top of peptide vial with alcohol swab
  2. Wipe top of BAC water vial with alcohol swab
  3. Draw desired amount of BAC water into syringe
  4. Insert needle into peptide vial at an angle
  5. Slowly let water run down the inside of the vial
  6. Do not spray directly onto powder

4. Allow to Dissolve

  • Let sit for 2-5 minutes
  • Powder will dissolve on its own
  • Gently swirl if needed—never shake
  • Solution should be completely clear

5. Label and Store

  • Write reconstitution date on vial
  • Note concentration (e.g., "5mg in 2mL = 2.5mg/mL")
  • Store immediately in refrigerator
  • Use within 4-6 weeks

Reconstitution Volume Guide

The amount of BAC water you add determines your concentration. More water = lower concentration = larger injection volumes per dose.

Common Reconstitution Volumes

Peptide AmountBAC Water AddedConcentration
5 mg1 mL5 mg/mL (5000 mcg/mL)
5 mg2 mL2.5 mg/mL (2500 mcg/mL)
10 mg1 mL10 mg/mL (10000 mcg/mL)
10 mg2 mL5 mg/mL (5000 mcg/mL)
10 mg2.5 mL4 mg/mL (4000 mcg/mL)

Choosing Your Volume

  • Higher concentration (less water): Smaller injection volumes, vial runs out faster
  • Lower concentration (more water): Larger injection volumes, easier to measure small doses

General rule: Use 1-2 mL for vials you'll finish within a month. Don't use so much water that your vial will take months to finish.


Dosing Calculations

The Master Formula

Dose (mcg) ÷ Concentration (mcg/mL) = Injection Volume (mL)

Converting to Syringe Units

Most insulin syringes are marked in "units." On a standard 1 mL insulin syringe:

  • 100 units = 1 mL
  • 10 units = 0.1 mL
  • 1 unit = 0.01 mL

Example Calculations

Example 1: BPC-157 (250 mcg dose)

  • Vial: 5 mg peptide
  • Added: 2 mL BAC water
  • Concentration: 5000 mcg ÷ 2 mL = 2500 mcg/mL

Calculation: 250 mcg ÷ 2500 mcg/mL = 0.1 mL = 10 units


Example 2: TB-500 (2.5 mg dose)

  • Vial: 10 mg peptide
  • Added: 2 mL BAC water
  • Concentration: 10000 mcg ÷ 2 mL = 5000 mcg/mL

Calculation: 2500 mcg ÷ 5000 mcg/mL = 0.5 mL = 50 units


Example 3: GHRP-6 (100 mcg dose)

  • Vial: 5 mg peptide
  • Added: 2.5 mL BAC water
  • Concentration: 5000 mcg ÷ 2.5 mL = 2000 mcg/mL

Calculation: 100 mcg ÷ 2000 mcg/mL = 0.05 mL = 5 units


Quick Dosing Tables

BPC-157 (5 mg vial + 2 mL BAC water = 2500 mcg/mL)

DoseVolumeSyringe Units
150 mcg0.06 mL6 units
250 mcg0.10 mL10 units
300 mcg0.12 mL12 units
500 mcg0.20 mL20 units

TB-500 (5 mg vial + 1 mL BAC water = 5000 mcg/mL)

DoseVolumeSyringe Units
1 mg0.20 mL20 units
2 mg0.40 mL40 units
2.5 mg0.50 mL50 units

GHRP/GHRH Peptides (5 mg vial + 2.5 mL BAC water = 2000 mcg/mL)

DoseVolumeSyringe Units
50 mcg0.025 mL2.5 units
100 mcg0.05 mL5 units
200 mcg0.10 mL10 units
300 mcg0.15 mL15 units

Unit Conversions

Weight Conversions

  • 1 mg (milligram) = 1000 mcg (micrograms)
  • 0.5 mg = 500 mcg
  • 0.25 mg = 250 mcg

Volume Conversions

  • 1 mL (milliliter) = 100 units on insulin syringe
  • 0.5 mL = 50 units
  • 0.1 mL = 10 units
  • 0.01 mL = 1 unit

Quick Reference

mcgmg
1000.1
2500.25
5000.5
10001.0
25002.5

Injection Technique Quick Guide

Subcutaneous Injection (Most Common)

  1. Clean injection site with alcohol swab
  2. Pinch fold of skin (abdomen is most common)
  3. Insert needle at 45-90° angle
  4. Inject slowly
  5. Withdraw needle and apply light pressure if needed
  6. Rotate sites with each injection

Site Rotation Pattern

  • Divide abdomen into quadrants
  • Rotate clockwise with each injection
  • Space injections at least 1 inch apart
  • Keep a mental or written log

Storage Quick Reference

Before Reconstitution (Lyophilized Powder)

  • Refrigerator: 18-24 months
  • Room temperature (<77°F): 60-90 days
  • Freezer: 2+ years

After Reconstitution (Solution)

  • Refrigerator: 4-6 weeks (most peptides)
  • Room temperature: Avoid—return to fridge immediately after drawing dose
  • Freezer: Never freeze reconstituted peptides

Storage Rules

  • Always refrigerate after reconstitution
  • Protect from light (keep in box or wrap in foil)
  • Never freeze reconstituted solution
  • Discard if cloudy or after 6 weeks

Common Mistakes to Avoid

During Reconstitution

  • ❌ Spraying water directly onto powder
  • ❌ Shaking the vial
  • ❌ Using sterile water instead of BAC water
  • ❌ Not allowing powder to fully dissolve

During Dosing

  • ❌ Drawing from vial without wiping stopper
  • ❌ Injecting air bubbles
  • ❌ Leaving vial out of refrigerator
  • ❌ Not rotating injection sites

During Storage

  • ❌ Freezing reconstituted peptides
  • ❌ Storing in direct light
  • ❌ Forgetting to label with date
  • ❌ Using past 6 weeks

Troubleshooting

Powder won't dissolve

  • Wait longer (up to 10 minutes)
  • Gently roll vial between palms
  • Water may be running down the side and not contacting powder—tilt vial slightly
  • Never shake vigorously

Solution looks cloudy

  • Wait a few more minutes—may still be dissolving
  • If cloudy persists after 10 minutes, peptide may be damaged
  • Do not use cloudy solutions

Solution has particles/floaters

  • Do not use
  • Contamination or degradation has occurred
  • Discard and start with fresh vial

Unsure if dose is accurate

  • Re-check your math
  • Verify concentration calculation
  • When in doubt, use the master formula: Dose ÷ Concentration = Volume

Printable Dose Calculator

Your Custom Calculation:

Peptide amount: _____ mg

BAC water added: _____ mL

Concentration = _____ mg ÷ _____ mL = _____ mg/mL (_____ mcg/mL)

Your dose: _____ mcg

Injection volume = _____ mcg ÷ _____ mcg/mL = _____ mL = _____ units


Summary Checklist

Before You Start:

  • Have all supplies ready
  • Workspace is clean
  • Know your target dose

Reconstitution:

  • Wipe vials with alcohol
  • Add BAC water slowly down the side
  • Wait for complete dissolution
  • Solution is clear (not cloudy)

After Reconstitution:

  • Label with date and concentration
  • Store in refrigerator immediately
  • Calculate dose before drawing

Each Use:

  • Wipe vial stopper
  • Draw correct dose
  • Return vial to refrigerator immediately
  • Rotate injection site

Frequently asked questions

How much bacteriostatic water should I add to a peptide vial?

For most 5 mg vials, 2 mL of bacteriostatic water yields a convenient 2.5 mg/mL concentration. For 10 mg vials, 2-2.5 mL is typical. The goal is to finish the vial within a month while keeping injection volumes between 0.05-0.5 mL for accurate dosing.

Can I shake the vial to dissolve the peptide faster?

Never shake a peptide vial. Vigorous shaking denatures the peptide structure and creates foam that damages the molecule, silently reducing potency. Instead, let the powder dissolve naturally over 2-5 minutes, or gently swirl or roll the vial between your palms if needed. Patience preserves potency.

How long does reconstituted peptide last in the refrigerator?

Most reconstituted peptides remain stable for 4-6 weeks when refrigerated at 36-46 degrees Fahrenheit. More fragile peptides last 2-3 weeks. Label every vial with the reconstitution date and discard solutions that become cloudy, contain particles, or pass the 6-week mark.

How do I calculate my peptide dose in syringe units?

Use the master formula: Dose (mcg) divided by Concentration (mcg/mL) equals injection Volume (mL). On a 1 mL insulin syringe, 100 units equals 1 mL, so multiply your mL by 100 to get units. Example: 250 mcg drawn from a 2500 mcg/mL solution equals 0.1 mL, which is 10 units on the syringe.

Why use bacteriostatic water instead of regular sterile water?

Bacteriostatic water contains 0.9% benzyl alcohol as a preservative that prevents bacterial growth in multi-use vials drawn from over several weeks. Sterile water has no preservative and is only safe for single-use preparations. Never use tap water or saline.

Why is my reconstituted peptide cloudy?

A cloudy solution after 10 minutes indicates the peptide may be damaged, contaminated, or improperly synthesized. Do not inject cloudy solutions or solutions with visible particles. Discard the vial and start fresh; the cost of replacement is less than the risk of injecting a degraded product.

Can I freeze reconstituted peptides to extend shelf life?

Never freeze reconstituted peptides. Ice crystals physically destroy the peptide structure, often irreversibly, even though the damage may not be visible. Only lyophilized (powder) peptides tolerate freezer storage. Refrigerate reconstituted solutions and use within 4-6 weeks.

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Written By

Editorial team. We cite published research; we are not licensed clinicians and content is not medically reviewed.

Peptide researchHealth writingEvidence synthesis

This article cites peer-reviewed research and medical literature. Click any reference to view the original source.

  1. 1

    Ó'Fágáin C, Colliton K (2023) Storage and Lyophilization of Pure Proteins Methods in Molecular Biology.

    PMID: 37647008DOI: 10.1007/978-1-0716-3362-5_19View on PubMed
  2. 2

    Frid AH, Kreugel G, Grassi G, et al. (2016) New Insulin Delivery Recommendations Mayo Clinic Proceedings.

    PMID: 27594187DOI: 10.1016/j.mayocp.2016.06.010View on PubMed
  3. 3

    Angkawinitwong U, Sharma G, Khaw PT, Brocchini S, Williams GR (2015) Solid-state protein formulations Therapeutic Delivery.

    PMID: 25565441DOI: 10.4155/tde.14.98View on PubMed

Medical Disclaimer

The information on this website is for educational purposes only and is not medical advice. The content creators are not doctors or medical professionals. This content should not be used to diagnose, treat, cure, or prevent any disease. Always consult with a qualified healthcare provider before starting any new supplement, medication, or health protocol. You assume all risks associated with using this information.