How to reconstitute HCG and read the units
HCG is measured in International Units (IU) rather than milligrams. Reconstitution works exactly like a peptide: the water sets an IU-per-mL concentration, and your dose becomes a volume you read as units.
- Sanitise the HCG vial stopper and the BAC-water vial with an alcohol swab and let them dry.
- Add the water slowly down the inside wall of the vial — this sets the IU/mL concentration.
- Swirl gently until fully dissolved; HCG is delicate, so do not shake.
- Enter your IU dose to read the units to draw on a U-100 syringe, then refrigerate the vial.
Worked example: a 5,000 IU vial at a 500 IU dose
A 5,000 IU vial reconstituted with 2 mL of BAC water, at a 500 IU dose:
- Concentration — 5,000 IU ÷ 2 mL = 2,500 IU/mL.
- Volume for your dose — 500 IU ÷ 2,500 IU/mL = 0.2 mL.
- Units to draw — 0.2 mL × 100 units/mL = 20 units on a U-100 syringe.
- Doses per vial — 5,000 IU ÷ 500 IU = 10 doses.
Enter your own vial IU, water, and dose above. Once reconstituted, HCG is kept refrigerated and used within the window on your label.
Frequently asked questions
How do I reconstitute HCG?
Add bacteriostatic water to the HCG vial to set a concentration in IU per mL, then draw your prescribed IU dose as a volume. For example, 5,000 IU in 2 mL is 2,500 IU/mL, so a 500 IU dose is 0.2 mL (20 units on a U-100 syringe). Follow the mixing volume your provider or pharmacy specifies.
Why is HCG measured in IU instead of mg?
HCG is a biological product dosed by activity, which is expressed in International Units (IU). The reconstitution math is the same as for a peptide — the water just sets an IU/mL concentration instead of mg/mL.
How should reconstituted HCG be stored?
Reconstituted HCG is generally kept refrigerated and used within the beyond-use window on your label or as directed by your pharmacy. Check the discard-by date and follow your product’s storage instructions.
Is this HCG calculator medical advice?
No. It is an educational estimation tool that does the arithmetic from your numbers and shows its work. It never prescribes, diagnoses, or recommends a dose. Always follow your licensed provider’s instructions.
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