Gonadotropin-releasing hormone (GnRH) · Formerly FDA-approved (diagnostic; brand withdrawn)

Gonadorelin

Approved (diagnostic)A genuine, formerly FDA-approved hormone with established diagnostic use, but its popular use to maintain testosterone or fertility is off-label with limited modern trial support.

A synthetic copy of the brain's gonadotropin-releasing hormone that tells the pituitary to release LH and FSH, historically used as a diagnostic agent.

✦ 2 min read · 2 sources

What it is

Gonadorelin is synthetic gonadotropin-releasing hormone (GnRH). The FDA had approved it (brand Factrel) for evaluating hypothalamic-pituitary-gonadal axis function via the GnRH stimulation test; the brand was later withdrawn from the market for commercial, not safety, reasons. Current U.S. supply is largely through compounding pharmacies.

How it works

GnRH from the hypothalamus normally signals the pituitary in pulses. Delivered in a pulsatile pattern, gonadorelin stimulates the pituitary to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which drive testicular testosterone production and sperm formation. Paradoxically, continuous (non-pulsatile) exposure desensitizes the receptor and suppresses LH/FSH instead.

What the evidence shows

Gonadorelin's ability to provoke LH and FSH release is well established and underpins its validated diagnostic GnRH-stimulation test, and pulsatile GnRH has a documented role in inducing ovulation in hypothalamic amenorrhea. However, robust modern controlled-trial evidence for its increasingly common off-label use to maintain testosterone or fertility in men on hormone therapy is limited. Its very short half-life (roughly 2–10 minutes) makes consistent pulsatile dosing practically challenging.

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The honest take

A genuine, formerly FDA-approved hormone with established diagnostic use, but its popular use to maintain testosterone or fertility is off-label with limited modern trial support.

Status & safety

Gonadorelin is a prescription product; with the original brand withdrawn, legitimate access is typically via a clinician and compounding pharmacy, and male hormone-support use is off-label. As GnRH, it falls under prohibited gonadotropin-releasing hormone agents in sport under WADA category S2. Use should be clinician-supervised given dosing complexity and the off-label nature of most current applications.

Summaries of published, third-party research for educational purposes. Not medical advice; not a claim of efficacy or safety for any use.

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