HomePeptides › Gonadorelin

Gonadorelin

GnRH, LHRH, Factrel

Tier 1 · FDA Approved
Class
GnRH agonist (native sequence)
Molecular target
GnRH receptor
Sequence / structure
pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2
Evidence tier
Tier 1 — FDA Approved
Category
Reproductive Axis
Emergency card
Signs something is wrong

Any new or unusual symptom after dosing. Because this compound has little or no human safety data, there is no established list of 'expected' effects to reassure you against — treat anything abnormal as a signal.

What to do now

Stop at the first clearly abnormal reaction and reassess. Keep the vial and lot number in case you need to describe what you actually took.

When it is an emergency

Any severe or fast-worsening symptom — difficulty breathing, chest pain, fainting, severe pain — is a 911 call regardless of the compound.

Any injection — every time

Allergic reaction: hives, swelling of the lips, tongue or throat, wheezing or dizziness can escalate to anaphylaxis within minutes — call 911 immediately. Site infection: spreading redness, heat, swelling, pus or fever is not wait-and-see; an abscess or cellulitis can need drainage or IV antibiotics. Unverified product: grey-market vials are frequently mislabelled or contaminated, so a reaction may be to endotoxin or the wrong contents, not the named compound.

This is not permission or instruction to use this compound. It is harm-reduction information for someone who has already decided to, so that a bad reaction is recognised and treated. When in doubt, get help — embarrassment is survivable.

Biology & mechanism

The native hypothalamic decapeptide. Its defining property is that pulsatility determines the outcome: delivered in physiological pulses roughly every 90 minutes it stimulates LH and FSH release, whereas continuous exposure desensitises and downregulates the receptor and suppresses the axis entirely. That paradox is the basis of the entire GnRH agonist drug class — leuprolide and its relatives are used for chemical castration precisely by exploiting continuous exposure. Native gonadorelin has a half-life of only two to four minutes.

What the research actually shows

Long-established as a diagnostic agent for pituitary gonadotropin reserve, and historically used with pulsatile pumps to induce fertility in hypogonadotropic hypogonadism.

Regulatory status

FDA-approved historically as a diagnostic agent (Factrel); US availability has been limited and products discontinued. Now largely supplied through compounding, an area under active FDA scrutiny. Prohibited in sport (WADA S2 for males).

Safety signals

The pulsatility paradox is the practical hazard: administration patterns that are not genuinely pulsatile can suppress the axis rather than stimulate it — the opposite of the intended effect. Headache, flushing, injection-site reactions.

Clinical trial dosing — what the studies actually used

Diagnostic: 100 mcg IV or SC. Fertility induction historically used pulsatile-pump delivery. Largely compounded now; US products discontinued.

Reported from clinical trials or FDA labelling as a matter of record. It is not a recommendation, and for unapproved compounds no dose has been shown safe or effective in humans.

We report study doses, not protocols

Above is what was administered in trials or on FDA labels, reported as fact. We do not convert it into a personal protocol, calculate a dose for your body weight, or tell you what to inject or how to reconstitute it — that decision belongs with a licensed physician. See our editorial policy.

References & further reading

Regulatory status changes. This page reflects our reading of public sources as of July 2026 and should be independently verified before it is relied upon.

Important notice Forge Bioenergy publishes scientific reference information only. Nothing on this site is medical advice, a therapeutic claim, or a recommendation to use any substance in humans. Many peptides described here are not approved by the FDA for any use, and several are approved only for narrow indications under prescription. We do not publish dosing, administration, or usage protocols. Consult a licensed physician before making any medical decision.