Gonadorelin
Synthetic GnRH, the brain’s signal to the pituitary to release LH and FSH; used on TRT as a substitute for hCG.
Not approved for use with TRT; the US diagnostic form (Factrel) is off the market; sold compounded or as a research chemical.
Used for
- Keeping testicular size and fertility on TRT (off-label)
- Hypothalamic hypogonadism (as a pump)
How it works
Stimulates the pituitary to release LH and FSH, which drive testosterone and sperm production in the testes. It lasts only minutes, and the pituitary responds to pulses: constant exposure switches it off (how leuprolide works).
Half-life: a few minutes
What the research shows
- Given by pump every 1.5–2 hours, it started sperm production in men with hypothalamic hypogonadism about as well as hCG/hMG (54 of 57 courses).
- In a 2025 series of men with congenital hypogonadism, the pump raised testosterone and testicular size; 27 of 45 men treated for over 6 months produced sperm.
- Twice- or thrice-weekly shots alongside TRT, the common use, have not been studied.
Dosing
Dosing isn’t listed on the public site. In the app, each published option is shown with its source (a drug label, a clinical guideline, a trial or community reports) and can be turned into a protocol you review.
Work out the units to draw for your vial →Side effects
- Injection-site reactions
- Headache, flushing
Cautions
- hCG has the human data for fertility on TRT; gonadorelin does not.
- Frequent dosing may blunt the pituitary rather than stimulate it.
- Prohibited in tested sports (WADA).
- Research-chemical vials have no quality control: purity, dose and sterility vary. Third-party testing helps but is no guarantee.
Storage
Unmixed powder: freezer or fridge, away from light.
Once mixed with bacteriostatic water: fridge; the common rule is to use it within 28 days.
There is no label or published stability data for this one, so treat these as habits, not limits.
Reference only, not medical advice. Written for this app from the cited research. Doses marked community-reported are not from trials.