What is HCG?
HCG (human chorionic gonadotropin) is a hormone that acts in the body very similarly to LH. LH is the signal that drives the testes to produce testosterone. That is exactly why HCG is used to keep the testes active and at their size, especially on and after a cycle when the body's own axis is suppressed.
How it works
HCG binds the LH receptors of the Leydig cells in the testes and triggers testosterone production there directly, bypassing the brain. This keeps the testes functional even when the brain is not sending its own LH because of external hormones.
That is why HCG helps against the typical testicular shrinkage on a cycle and eases recovery afterwards.
What you need
- The HCG vial (lyophilized powder, labeled in IU).
- Bacteriostatic water for mixing.
- U-100 insulin syringes, alcohol swabs.
Mixing and units
HCG is given in IU (international units), not in mg. Vials are usually labeled with their total IU (for example 5000 IU).
- Example: a 5000 IU vial with 5ml bacteriostatic water gives 1000 IU per ml.
- On a U-100 insulin syringe 1000 IU is then 100 units.
- 250 IU is accordingly 25 units, 500 IU is 50 units.
Just add the water and let it dissolve.
Dosing (in IU)
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Injection
Subcutaneous into the subcutaneous fat with the short insulin needle. Disinfect the site, pinch a skin fold, inject slowly, rotate sites.
What the research shows
A study (Hsieh, 2013) showed that low-dose HCG (250 IU every other day) added to testosterone therapy preserved sperm production. That supports its use to keep testicular function active while the body's own axis is suppressed.
Side effects
- Rise in estrogen (via more testosterone in the testes), with gyno risk at higher doses.
- With high-dose continuous use the sensitivity of the testes can drop.
- Mood swings, acne, local reactions.
Practice
- Dose low and regular, not rare and high.
- With an estrogen rise, consider an aromatase inhibitor (see anastrozole/exemestane).
- Banned in official competition for men (WADA S2).
Storage
Before mixing the powder is robust, normal room temperature (around 20 to 25 degrees) is fine, ideally kept in the dark. After mixing, keep in the fridge (2 to 8 degrees), do not freeze. It stays good there for at least 8 to 10 weeks with barely any loss of potency, in practice considerably longer. Swirl or shake to mix, both are fine.