Gonadorelin
Aliases: GnRH · Factrel · LHRH
Last verified: 2026-09-23
The short version
Synthetic GnRH (decapeptide identical to human) — approved as a pituitary diagnostic; in pulsatile use treats hypogonadism/infertility. In the peptide community used to "restart" the HPTA axis.
Identity & type
- Molecular type
- analog
- Origin
- Synthetic GnRH (decapeptide identical to human) — approved as a pituitary diagnostic; in pulsatile use treats hypogonadism/infertility.
Mechanism of action
Pituitary GnRH receptor agonist → LH/FSH. Continuous dosing paradoxically suppresses the axis (desensitization).
Dosing & routes
Official / clinical context
Approved drug — indications, dosing and warnings are defined by the official label. Diagnostics: 100 mcg IV/SC. Pulsatile therapy: 5–20 mcg every 90–120 min via pump.
Regulator-approved labeling and published study designs — never a recommendation.
Community-reported practice
Diagnostics: 100 mcg IV/SC. Pulsatile therapy: 5–20 mcg every 90–120 min via pump. Used for diagnostics and pulsatile GnRH treatment; biohackers add it as "HPTA maintenance" — preserved testicular function is reported, but evidence is weak.
Unverified self-reports. Not medical advice. Not endorsement.
Expected effects (community)
Used for diagnostics and pulsatile GnRH treatment; biohackers add it as "HPTA maintenance" — preserved testicular function is reported, but evidence is weak.
Protocol — official vs community
Official / label
Two labeled uses. Diagnostic: 100 mcg SC/IV once to assess pituitary gonadotrope reserve. Therapeutic (hypogonadotropic hypogonadism/infertility): pulsatile 5–20 mcg SC every 90–120 minutes via infusion pump to mimic the physiological GnRH pulse.
- 01Pulsatile therapy: pump dose adjusted against LH/FSH response and gonadal steroid levels
Duration: Diagnostic: single dose. Pulsatile therapy: months, continued until fertility goal met or ovulation/spermatogenesis achieved.
Continuous (non-pulsatile) dosing desensitizes the pituitary and suppresses LH/FSH — the opposite of the pulsatile goal. The pump requirement is why this therapy largely stayed in specialist centers.
Community (anecdotal)
Gray-market vials (often sold as 'HCG alternative') used at 100–200 mcg SC a few times weekly, loosely modeled on the diagnostic dose rather than the pulsatile protocol.
- Cycle:
- Weeks, usually framed around post-cycle therapy (PCT).
- Break:
- None systematic.
The community 'HPTA restart' rationale ignores the core pharmacology: GnRH works only in pulses; bolus dosing without pump hardware is a pharmacologically different (and largely unproven) intervention.
Human evidence
Approved for decades; standard in reproductive endocrinology.
Preclinical evidence
The preclinical phase was completed and submitted to regulators as part of registration; pharmacology and toxicology details are part of the official label.
Known risks
- Mild: headache, nausea, injection-site pain.characterized
Teal: characterized in clinical/labeling contexts. Amber: theoretical or reported outside controlled settings.
Unknowns & evidence gaps
- Real-world data outside controlled trials