Vialwise
EN

Gonadorelin

Gonadorelin is a synthetic copy of gonadotropin-releasing hormone (GnRH), the brain hormone that tells the pituitary to release LH and FSH. Given in pulses, it switches the reproductive hormones on; given continuously, it switches them off. It is used as a test of pituitary function, in pump-based fertility treatment, and in cattle breeding.

Approved in some countriesWADA Prohibited at all times in males (S2.2.1)Checked October 2026
Open the Gonadorelin calculatorSources

Approval status

No human gonadorelin product is currently marketed in the US: the FDA lists Factrel and Lutrepulse as discontinued. In the UK, a gonadorelin injection is licensed as a diagnostic test of pituitary function. Veterinary gonadorelin injections such as Factrel (Zoetis) are FDA-approved for cattle and labeled not for human use.34527

What it’s used or studied for

  • Approved use

    Diagnostic test of how well the pituitary releases LH and FSH (injection licensed in the UK by the MHRA).5

  • Approved use

    Given in pulses by a small pump to induce ovulation in women with hypothalamic amenorrhea (Lutrepulse; approved by Health Canada, and by the FDA before its US discontinuation).648

  • Human studies

    Given in pulses by pump to men with congenital hypogonadotropic hypogonadism to start sperm production; it works in most men treated.910

  • Animal & lab only

    Veterinary only: FDA-approved for cattle, to treat ovarian follicular cysts and to time ovulation for fixed-time insemination. This is not a human use.2

  • No studies

    Promoted online for men on testosterone therapy to keep the testes active; no trials have tested this, and GnRH normally needs pulsed delivery to work.11

Each label shows how strong the evidence is: an approved use, human studies, animal or lab studies only, or a popular claim with no published studies. Being studied is not the same as being proven safe or effective.

Side effects

Common

  • Pain
  • Skin swelling or itching
  • Hardening at the injection site
  • Irritation, inflammation or infection at a pump needle site
  • Headache
  • Dizziness
  • Nausea or abdominal discomfort
  • Flushing

Serious or rare

  • Severe allergic reactions (anaphylaxis) and bronchospasm
  • Ovarian hyperstimulation (rare, with pump treatment)
  • Multiple pregnancy (with pump treatment)
  • Antibodies that stop it working (rare, with long-term use)

These come from the UK diagnostic label and the Canadian Lutrepulse label; most reported effects are mild and local. A meta-analysis of pump treatment in women found ovarian hyperstimulation was rare and mild.568

Cautions

  • Continuous exposure to GnRH shuts down LH and FSH release instead of raising it.11
  • Not for use in known or suspected pregnancy (UK diagnostic label).5
  • The Lutrepulse label says it should not be used by women with ovarian cysts or hormone-dependent tumors, and pump treatment needs ultrasound monitoring because of the risk of multiple pregnancy.6
  • Veterinary gonadorelin products are labeled for use in animals only, not for human use.2

Sources

  1. PubChem CID 638793: Gonadorelin
  2. FDA veterinary label: Factrel (gonadorelin hydrochloride) injection for cattle, NADA 139-237 (DailyMed)
  3. Drugs@FDA: NDA 018123, Factrel (gonadorelin hydrochloride), discontinued
  4. Drugs@FDA: NDA 019687, Lutrepulse (gonadorelin acetate), discontinued
  5. UK SmPC: Gonadorelin powder for solution for injection (Esteve Pharmaceuticals), revised 2022
  6. Health Canada product monograph: Lutrepulse (gonadorelin acetate for injection), revised 2016
  7. WADA 2026 Prohibited List
  8. Tranoulis A et al. Efficacy and safety of pulsatile GnRH therapy in hypothalamic amenorrhea: systematic review and meta-analysis (Fertil Steril, 2018)
  9. Dwyer AA et al. Current landscape of fertility induction in males with congenital hypogonadotropic hypogonadism (Ann N Y Acad Sci, 2024)
  10. Zhang L et al. The pulsatile gonadorelin pump induces earlier spermatogenesis than cyclical gonadotropin therapy in CHH men (Am J Mens Health, 2019)
  11. Cretu AM et al. Emerging peptide and neuroendocrine strategies for TRT-induced reproductive suppression (Front Reprod Health, 2026)

Spotted a mistake on this page? Report it. The email opens with the peptide and vial already filled in.