Library / Hormonal

Gonadorelin

Also known as GnRH, LHRH, Factrel, Lutrepulse

Approved medicine

Synthetic version of natural gonadotrophin releasing hormone. Was approved for diagnostic testing and pulsatile fertility treatment; no longer marketed in Australia or the US.

Not approved in Australia. Gonadorelin is not on the Australian Register of Therapeutic Goods and is no longer marketed in the United States. Only a prescriber can decide whether a medicine suits you and at what dose. This page is information, not a recommendation.

Background

Synthetic copy of natural gonadotrophin releasing hormone (GnRH), a 10 amino acid hypothalamic hormone whose structure was worked out in 1971 by Andrew Schally's group. As Factrel it was FDA approved in 1982 for human diagnostic use; that product is now discontinued, and current US gonadorelin labels are veterinary (cattle) products.

How it is thought to work

Binds GnRH receptors on the pituitary. Given in short pulses it makes the pituitary release LH and FSH, restoring the natural hormone rhythm; given continuously it does the opposite and suppresses LH and FSH.

What is claimed, and the evidence

Claim	Evidence	Notes
Testing pituitary LH and FSH reserve	Approved use	Former FDA approved diagnostic use (Factrel, 1982); the human product is discontinued and not on the ARTG.
Inducing ovulation in women with hypothalamic amenorrhoea or hypogonadotrophic hypogonadism using a pulsatile pump	Small human studies	Case series and cohorts report ovulation in over 90% of cycles and mostly single egg release, with a low multiple pregnancy rate.
Maintaining testicular size and natural testosterone during testosterone or steroid use	No published evidence	Popular online claim; intermittent injections do not mimic the 60 to 90 minute pulses used in clinical studies, and no trials support this use.

Side effects

Effect	How often	Notes
Multiple pregnancy Serious	Uncommon	7 of 100 pregnancies in one large pulsatile series; lower than with gonadotrophin injections.
Miscarriage Serious	Common	28 of 100 pregnancies in the same series, higher in women with polycystic ovaries; not necessarily caused by the drug.
Suppression of LH, FSH and sex hormones with continuous or frequent dosing	Frequency unknown	Expected pharmacology of GnRH receptor overstimulation.
Injection or pump site reactions and allergic reactions	Frequency unknown	Current human label data were not available for review.

Warnings

No human gonadorelin product is currently on the ARTG or marketed in the US; products sold online may be veterinary or unregulated.
Veterinary gonadorelin products are labelled for cattle only.
Unapproved products bought online or from compounders may be contaminated, non sterile, underdosed, overdosed or contain a different substance; the TGA warns their labelling may be inaccurate and it has received reports of severe allergic reactions and hospitalisations.

Regulatory status

Australia: Not found on the ARTG. Schedule 4 in the Poisons Standard.
United States: Previously FDA approved (Factrel) as a diagnostic test of pituitary function; no current human product found in Drugs@FDA (discontinued). Current marketing status Not verified.

Sources

Also in Hormonal

From the VialOwl library, reviewed 26 September 2026. For education and general information. It is not medical advice and not a recommendation to use Gonadorelin.