Gonadorelin
Endogenous GnRH peptide — FDA-approved for hypogonadism diagnosis, used clinically to preserve testicular function during TRT.
Research facts
| Half-life | ~2–4 minutes |
|---|---|
| Route | SubQ / IV |
| Typical dose | 25–100 mcg pulse dosing |
| Frequency | Pulsatile (every 60–120 minutes physiologically) or twice-daily SubQ clinically |
| Solvent | Bacteriostatic water |
| pH | 5.5–7.5 |
| Stability | 30 days at +4°C |
Mechanism of action
Gonadorelin is the synthetic form of endogenous GnRH — a decapeptide produced by hypothalamic KNDy neurons (the same neurons regulated by kisspeptin). Pulsatile gonadorelin stimulates pituitary GNRHR to release LH and FSH, maintaining HPG axis integrity. It is used clinically as an FDA-approved diagnostic test for hypothalamic-pituitary function, and increasingly used alongside TRT (testosterone replacement therapy) to preserve intratesticular testosterone, spermatogenesis, and testicular volume — effects that exogenous testosterone alone suppresses. When administered twice daily SubQ in physiological doses, it maintains pulsatile LH secretion that preserves testicular function.
Documented effects (research-model)
- FDA-approved diagnostic for hypothalamic-pituitary function
- Preserves testicular volume and spermatogenesis during TRT
- Restores HPG axis function post-anabolic steroid use
- Ovulation induction in hypothalamic amenorrhoea
- Male fertility preservation during androgen therapy
- Maintains intratesticular testosterone (fertility protection)
Research protocols
| Protocol | Dose | Frequency | Cycle | Vial |
|---|---|---|---|---|
| TRT Adjunct | 100 mcg twice daily SubQ | Twice daily (morning and evening) | Concurrent with TRT | 10mg / 10mL BAC water |
Research context only. Not medical advice. Consult a qualified healthcare professional before any protocol decision.
Synergies
- Kisspeptin-10 HIGH
Kisspeptin stimulates GnRH release (upstream); gonadorelin is GnRH itself. Used together in HPG axis restoration protocols.
Myths & misconceptions
Evidence gaps
- Optimal dosing schedule for TRT adjunct use not established in large RCTs.
- Long-term effects on pituitary receptor sensitivity with chronic dosing.
- Comparison data with hCG for testicular preservation outcomes.
Safety notes
Well-tolerated at physiological doses. Rare: injection site reactions, headache. High doses/continuous infusion leads to receptor downregulation (basis of GnRH agonist use in prostate cancer). Research and clinical use require monitoring of LH, FSH, testosterone.
Biomarkers to monitor
Primary-source citations
- PMID 22933541 — Gonadorelin versus hCG for preservation of testicular function during testosterone replacement (J Clin Endocrinol Metab. 2012)
Frequently asked
What is Gonadorelin?
Gonadorelin (GnRH — Gonadotropin-Releasing Hormone) is a research compound classified in our library as Tier A — Reproducible human RCT data.. Endogenous GnRH peptide — FDA-approved for hypogonadism diagnosis, used clinically to preserve testicular function during TRT.
What is the evidence tier for Gonadorelin?
We classify Gonadorelin as Tier A: Reproducible human RCT data. See our full peptide evidence tiers explainer for how we assign S/A/B/C/D.
What is the research dose of Gonadorelin?
For Gonadorelin, typical research dose is 25–100 mcg pulse dosing, route is SubQ / IV, half-life is ~2–4 minutes. Protocols vary by research goal — see the protocols section on this page for standard and advanced dosing schedules. Research use only, not medical advice.
What does Gonadorelin stack well with?
Gonadorelin stacks well with Kisspeptin-10. Kisspeptin stimulates GnRH release (upstream); gonadorelin is GnRH itself. Used together in HPG axis restoration protocols.
Is Gonadorelin safe?
Well-tolerated at physiological doses. Rare: injection site reactions, headache. Research context only — no compound on this site is approved for human therapeutic use unless explicitly noted.