What is HCG?
Human Chorionic Gonadotropin (HCG) is a glycoprotein hormone naturally produced during pregnancy. In clinical settings, synthetic HCG is used for multiple indications: fertility treatments in both men and women, testosterone replacement therapy (TRT) support to maintain testicular function and fertility, and treatment of hypogonadism.
Why IU Instead of mg?
HCG is measured in International Units (IU) rather than milligrams because its biological activity varies by preparation. A vial labeled "5,000 IU" contains enough active hormone to produce 5,000 international units of biological effect. This is why our calculator defaults to IU for HCG — it matches how vials are actually labeled and how doses are prescribed.
How to Reconstitute HCG
HCG is typically supplied as a lyophilized powder with a separate vial of diluent or bacteriostatic water. HCG is more fragile than many peptides — handle gently.
- 5,000 IU vial → 2 mL BAC water (2,500 IU/mL)
- 10,000 IU vial → 5 mL BAC water (2,000 IU/mL)
- 11,000 IU vial → 5 mL BAC water (2,200 IU/mL)
Common HCG Protocols
Dosing varies significantly by indication. For TRT support, common protocols include 250–500 IU every other day or 500–1,000 IU twice weekly. For fertility, higher doses may be used under direct medical supervision. Always follow your prescriber's specific protocol.
Storage — More Sensitive Than Most Peptides
HCG is more temperature-sensitive than many peptides. Both reconstituted and unreconstituted HCG should be stored in the refrigerator at 2–8°C (not the freezer). Once mixed, use within 30 days. Some pharmacies recommend 60 days with BAC water, but 30 is the conservative standard. Never freeze HCG.
Side Effects and Monitoring
HCG can increase estrogen levels through increased intratesticular testosterone production. Regular blood work monitoring estradiol (E2) levels is recommended. Some protocols include an aromatase inhibitor if estrogen rises excessively. Water retention and mood changes are possible at higher doses.
HCG is a prescription medication. This information is for educational purposes only. Consult a licensed healthcare provider.