Gonadorelin (GnRH)

Also known as: gonadorelin, GnRH, LHRH, gonadotropin-releasing hormone

Hormone RestorationSexual Well-Being

In plain English

Gonadorelin is a copy of the natural brain hormone that tells the pituitary gland to release the signals driving testosterone and fertility. When given in a pulsing pattern it can stimulate the body's own hormone production. In men's hormone care it is sometimes used to help maintain testicular function and fertility. It is given by small injection under the skin or as a nasal spray.

The science

Gonadorelin is synthetic gonadotropin-releasing hormone (GnRH). Physiologically, pulsatile GnRH stimulates pituitary release of LH and FSH; when delivered in a pulsatile fashion it can restore gonadotropin secretion, whereas continuous exposure paradoxically desensitizes and suppresses the axis. In men with congenital hypogonadotropic hypogonadism, pulsatile GnRH (pump) induces spermatogenesis at least as effectively as, and often earlier than, combined gonadotropin (hCG/hMG) therapy, with fewer estrogenic side effects (Mao 2018; meta-analysis 2020). Its very short half-life makes steady dosing challenging outside a pump, and compounded subcutaneous/nasal formulations used adjunctively during testosterone therapy (to preserve testicular volume/fertility) are largely off-label with limited controlled data for that specific use. FDA-approved gonadorelin historically existed for diagnostic testing; current compounded products are not FDA-approved formulations. Adverse effects are generally mild (injection-site reactions, headache).

References

• Comparative study, 2019 (pulsatile gonadorelin pump vs cyclical gonadotropin in congenital hypogonadotropic hypogonadism)
• Systematic review/meta-analysis, World J Mens Health 2020 (GnRH vs gonadotropin therapy)