How much BAC water do I add to a 5000 mg HCG vial?

For the standard ASCEND research protocol, add 2 mL of bacteriostatic water to a 5000 mg HCG vial. This yields 2500 IU/mL.

What concentration does 2 mL BAC water give for 5000 mg HCG?

A 5000 mg HCG vial reconstituted with 2 mL of bacteriostatic water yields 2500 IU/mL. A 250 IU dose then requires 0.1 mL (10 IU on a 100-unit insulin syringe).

What size insulin syringe should I use for HCG?

For a 250 IU dose (10 IU draw), a 30-unit (0.3 mL) U-100 insulin syringe gives the finest resolution. A 100-unit syringe also works.

RECONSTITUTION GUIDE

How Much BAC Water for HCG?

Q: Can I use sterile water instead of bacteriostatic water for HCG?

Bacteriostatic water (0.9% benzyl alcohol) is preferred because it inhibits bacterial growth and allows multi-dose use of the reconstituted vial. Sterile water lacks preservative properties and accelerates peptide degradation once the vial is opened.

Q: How long is HCG stable once reconstituted with BAC water?

Most research peptides remain stable for approximately 28 days when reconstituted with bacteriostatic water and stored at 2–8°C protected from light. Refer to peptide-specific stability data for any deviation from this baseline.

Quick answer: Add 2 mL of bacteriostatic water to a 5000 mg HCG vial. This yields a concentration of 2500 IU/mL. A standard 250 IU research dose then requires 0.1 mL (10 IU on a 100-unit insulin syringe).

250 IU draw on a 100-unit insulin syringe

Concentration by BAC water volume

Concentration and 250 IU draw volume at common BAC water volumes for a 5000 mg vial.

BAC water	Concentration	Dose volume	Draw
1 mL	5000 IU/mL	0.05 mL	5 IU
2 mL Standard	2500 IU/mL	0.1 mL	10 IU
3 mL	1666.67 IU/mL	0.15 mL	15 IU
5 mL	1000 IU/mL	0.25 mL	25 IU

Dose volume at the standard 2500 IU/mL concentration

How draw volume changes if you vary the dose at the standard 5000 mg + 2 mL reconstitution.

Dose	Volume	IU draw (100u)
125 IU	0.05 mL	5 IU
250 IU Std	0.1 mL	10 IU
375 IU	0.15 mL	15 IU
500 IU	0.2 mL	20 IU
750 IU	0.3 mL	30 IU

Reconstitution steps

Wipe the top of both the HCG vial and the bacteriostatic water vial with alcohol swabs.
Draw 2 mL of bacteriostatic water into a sterile syringe.
Inject the water slowly down the inside glass wall of the HCG vial. Do not aim directly at the powder.
Swirl gently until fully dissolved. Never shake.
Refrigerate at 2–8°C protected from light. Allow to reach room temperature before each draw.

Supplies needed

HCG 5000 mg lyophilized vial
2 mL bacteriostatic water (0.9% benzyl alcohol)
100-unit (1 mL) U-100 insulin syringe
Alcohol swabs
Sharps container for disposal

10,000 IU vial reconstitution

Standard reconstitution volumes and 250 IU draw for the 10,000 IU vial size.

Vial size	BAC water	Concentration	250 IU draw
5,000 IU Standard	2 mL	2500 IU/mL	0.1 mL (10 IU)
5,000 IU	5 mL	1000 IU/mL	0.25 mL (25 IU)
10,000 IU	2 mL	5000 IU/mL	0.05 mL (5 IU)
10,000 IU	5 mL	2000 IU/mL	0.125 mL (12.5 IU)
10,000 IU	10 mL	1000 IU/mL	0.25 mL (25 IU)

About HCG reconstitution

HCG (human chorionic gonadotropin) is a glycoprotein hormone supplied as a lyophilized white powder. It is more fragile than small peptides and requires careful reconstitution: inject bacteriostatic water slowly down the side of the vial and swirl very gently. Never shake -- aggressive mixing can denature the protein structure and reduce potency.

The 5,000 IU vial reconstituted with 2 mL is the most common research configuration, yielding 2,500 IU/mL. This produces a very small draw volume for typical 250–500 IU doses (0.1–0.2 mL), which is why some researchers prefer the 5 mL reconstitution for easier measurement. The 10,000 IU vial reconstituted with 5 mL or 10 mL is also common when splitting doses over a longer protocol period.

Reconstituted HCG should be stored at 2–8°C and used within 30 days. Because HCG is a protein hormone rather than a small peptide, it is more susceptible to temperature-related degradation. Do not leave reconstituted vials at room temperature for extended periods, and never freeze the solution.

Last reviewed: June 2026

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Frequently asked

How much BAC water do I add to a 5000 IU HCG vial?

The standard protocol is 2 mL of bacteriostatic water for a 5000 IU HCG vial, yielding 2500 IU/mL. A 250 IU dose then requires 0.1 mL (10 IU on a 100-unit syringe). Some researchers use 5 mL for 1000 IU/mL, which gives a larger, easier-to-measure 0.25 mL draw for the same 250 IU dose.

How much BAC water do I add to a 10,000 IU HCG vial?

For a 10,000 IU HCG vial, common reconstitution volumes are 2 mL (5000 IU/mL), 5 mL (2000 IU/mL), or 10 mL (1000 IU/mL). The 10 mL option is often preferred as it gives a 0.25 mL draw for a 250 IU dose -- easier to measure accurately than the 0.05 mL draw from the 2 mL reconstitution.

What concentration does 2 mL BAC water give for a 5000 IU HCG vial?

A 5000 IU HCG vial reconstituted with 2 mL of bacteriostatic water yields 2500 IU/mL. A 250 IU dose requires 0.1 mL (10 IU on a 100-unit syringe). A 500 IU dose requires 0.2 mL (20 IU).

Can I use sterile water instead of bacteriostatic water for HCG?

Bacteriostatic water is strongly preferred for HCG because multi-dose use is typical across research protocols. Sterile water lacks the benzyl alcohol preservative, meaning the reconstituted vial must be used in a single session. For HCG specifically, this wastes significant product given typical vial sizes.

How long is HCG stable once reconstituted with BAC water?

Reconstituted HCG stored at 2–8°C is stable for up to 30 days. As a protein hormone rather than a small peptide, HCG is sensitive to temperature fluctuations. Keep reconstituted vials continuously refrigerated and do not freeze the solution.

Why is my HCG draw volume so small?

At the standard 2500 IU/mL concentration (5000 IU + 2 mL), a 250 IU dose is only 0.1 mL (10 IU on a 100-unit syringe). This is a very small volume. To get a larger, more manageable draw, reconstitute the same 5000 IU vial with 5 mL instead -- this gives 1000 IU/mL and a 0.25 mL draw for the same 250 IU dose.

How do I reconstitute HCG without damaging it?

Inject bacteriostatic water slowly down the inside glass wall of the vial -- never directly onto the powder. Swirl very gently in a circular motion until dissolved. Never shake the vial. HCG is a protein hormone and more fragile than small synthetic peptides; mechanical stress can denature it and reduce potency.

What size syringe should I use for HCG?

At 2500 IU/mL, a 250 IU dose is only 0.1 mL -- use a 0.3 mL or 0.5 mL low-dead-volume insulin syringe for the best accuracy. If you reconstituted with more water (e.g. 5 mL for 1000 IU/mL), a standard 100-unit syringe works well for the resulting 0.25 mL draw.

For research use only. Not medical advice. Consult a qualified healthcare provider before using any peptide compound. Reconstitution parameters cross-referenced with independent 3rd-party analytical laboratories. · ASCEND · ascendpeptide.org