Gonadorelin (GnRH) Reconstitution Calculator

Gonadorelin is a synthetic decapeptide that is chemically identical to your body's own GnRH (gonadotropin-releasing hormone), the signal that tells the pituitary to release LH and FSH. It was originally an FDA-approved diagnostic drug (Factrel) for testing pituitary function, but today it's mainly supplied as a compounded prescription and used off-label alongside TRT to keep the testes working. It is a peptide hormone, not a steroid.

Gonadorelin can raise testosterone, but only indirectly and only if timed correctly. Because it clears the blood in about 2–4 minutes, it must be given in pulses to briefly hit the pituitary and trigger an LH/FSH release, which then signals the testes — mimicking the body's natural rhythm. Given continuously instead of in pulses, it does the opposite: the receptors downregulate and hormone output is suppressed, which is why dosing frequency matters so much.

Gonadorelin and hCG both protect testicular function on TRT but act at different levels: gonadorelin replaces the upstream GnRH signal (stimulating both LH and FSH, so it also supports sperm production), while hCG skips ahead and directly mimics LH at the testes with a much longer half-life. Triptorelin is a long-acting GnRH superagonist used to suppress hormones, essentially the opposite goal, and enclomiphene/clomid are oral SERMs that raise LH by a different route. None are interchangeable.

Reconstitute the lyophilized powder with bacteriostatic water: for a 2 mg vial, adding 4 mL gives 0.5 mg/mL, so a 100 mcg amount draws to 0.2 mL (20 units on a U-100 syringe); more water lowers the concentration for easier small doses. And yes, storage matters — the dry powder is stable cool, but once reconstituted it should be refrigerated (roughly 2–8 °C) and used within a few weeks, since gonadorelin in solution degrades over time. Compounded vials from a pharmacy follow the storage on their label.

There's no currently marketed FDA-approved gonadorelin product — the original Factrel was withdrawn for commercial reasons, so what's used now is compounded by prescription, and its TRT/fertility use is off-label without large trials. It's not a controlled substance and generally has a mild side-effect profile (injection-site reactions, headache, flushing), but compounded products carry potency and sterility variability, and it's WADA-banned for tested male athletes. Because it's meant to be prescribed and monitored, testosterone, fertility, or testicular-shrinkage concerns should go through a clinician, not self-dosing.