Gonadorelin (compounded)
GnRH (native)
Also Compounded gonadorelin, GnRH, Gonadotropin-releasing hormone, LHRH, Factrel, Lutrepulse
- Evidence
- CAnimal and cell studies
- FDA status
- Not approvedas of 2026-10-26
- Route
- Injection
- Studies cited
- 1 human0 animal or cell
A pharmacy-made injection that clinics give men on testosterone to keep the testicles from shrinking. No trial has tested it for that.
Sold for
Compounded gonadorelin is sold by men's-health clinics as an injection taken alongside testosterone to prevent testicular shrinkage and preserve fertility, a role hCG used to fill.
Studies say
Pulsatile GnRH works in men whose pituitary is intact but unstimulated, but no trial has tested intermittent gonadorelin injections in men on testosterone therapy, so the grade is C.
Why grade C. For the use it is compounded for, keeping testicular size and fertility during testosterone replacement, there are no controlled trials. The human evidence in the citations is a meta-analysis of seven studies (420 men) of pulsatile GnRH pumps in congenital hypogonadotropic hypogonadism, a different condition treated with a different delivery method. 1
FDA. Gonadorelin was once sold as the FDA-approved products Factrel (a diagnostic) and Lutrepulse (a pump-delivered fertility treatment), both now discontinued in the United States, and no FDA-approved gonadorelin product is marketed as of 2026-10-26. The gonadorelin used alongside testosterone therapy is compounded and has no approved indication for that use. 3
Written from 3 cited sources. Last refreshed 2026-10-27. Not physician reviewed.
What this means for you
- What people take it for
- Keeping testicle size and fertility during testosterone treatment.
- Can a US doctor prescribe it?
- No. The approved gonadorelin products are discontinued, and the version used here is made up by a pharmacy.
- Properly tested in people?
- Not properly: animal or lab studies, or small uncontrolled human reports. The only data are a review of seven studies (420 men) on a different condition.
Evidence checklist
- Randomised controlled trial No trial in men on testosterone therapyno
- Human study over 100 people Meta-analysis of 420 men, different conditionyes
- More than one research group Evidence is pooled studies of pump deliveryno information
- Clinical outcomes, not surrogate markers Testicular volume, sperm, pregnancy in CHHyes
- Human safety data beyond case reports Allergic reactions seen; injection untestedno
Drawn from the cited studies below. A dash means the sources give no information.
What it is
Gonadorelin is synthetic gonadotropin-releasing hormone (GnRH), the ten-amino-acid peptide the hypothalamus releases in pulses to make the pituitary secrete LH and FSH. It is identical to the natural hormone and is cleared from the blood within minutes. 2
Compounding pharmacies, including 503B outsourcing facilities, supply gonadorelin injections to clinics that prescribe it with testosterone. Demand rose after 2023, when the FDA restricted compounding of hCG, the drug clinics had used for the same purpose. 3
How it works
Testosterone replacement switches off the body's own GnRH, LH and FSH, so the testes stop making testosterone and sperm and shrink. The idea behind compounded gonadorelin is to replace the missing GnRH signal so the pituitary keeps releasing LH and FSH. Physiology complicates this: GnRH only works when delivered in pulses roughly every 90 to 120 minutes, which is why the approved fertility product used a programmable pump, and continuous or infrequent exposure desensitizes the receptor. Whether one or two subcutaneous injections a day reproduces the pulse pattern is untested. 21
What human research shows
The only human data in the citations concern men with congenital hypogonadotropic hypogonadism, who lack GnRH from birth. A 2021 meta-analysis of seven studies (420 men) found pulsatile GnRH via pump produced larger testicular volume and sperm appeared about five months earlier than with gonadotropin injections, while rates of sperm detection, sperm concentration and partner pregnancy were no different. Allergic reactions were more common with GnRH. 1
No trial has studied gonadorelin injections in men taking exogenous testosterone, and no trial has compared it with hCG for that purpose. 13
| Study | Model | Finding |
|---|---|---|
| Pulsatile GnRH vs gonadotropins meta-analysis | Humans, 7 studies, n=420 men with congenital hypogonadotropic hypogonadism | Larger testicular volume and earlier spermatogenesis with pulsatile GnRH; no difference in sperm counts or pregnancy rate. 1 |
| Pulsatile GnRH in hypogonadotropic hypogonadism | Humans, clinical series using programmable pumps | Pulse delivery restores LH and FSH secretion when the pituitary is intact. 2 |
Safety
In the pulsatile GnRH studies the main adverse events were allergic reactions at the infusion site. Gonadorelin is a natural hormone with a short half-life, so systemic toxicity at physiological doses is not expected. Unknowns include whether non-pulsatile injection suppresses the pituitary over time instead of stimulating it, and the quality and sterility of compounded product, which varies by pharmacy. 13
Questions for your clinician
- Is there any controlled human trial for the use I have in mind with testosterone therapy?
- How does gonadorelin compare with hCG for preserving fertility?
- How is the compounding pharmacy's product tested for sterility and purity?
Questions people ask
Is compounded gonadorelin FDA-approved?
No. The approved gonadorelin products were discontinued, and compounded versions are made without an approved indication. Using it with testosterone therapy is off-label by definition because there is no label. 3
Does gonadorelin replace hCG for men on testosterone?
That is the intent, but no trial has compared them in this setting. hCG acts directly on the testes; gonadorelin acts on the pituitary and depends on pulsed delivery, which daily injections may not reproduce. 12
What does the research actually show?
In men born without GnRH, pump-delivered pulsatile GnRH restores sperm production and does so a little faster than gonadotropin injections, based on 420 men across seven studies. There is no equivalent evidence for men on testosterone. 1
Citations
- 2021, World J Mens Health: pulsatile GnRH versus gonadotropin therapy in congenital hypogonadotropic hypogonadism, meta-analysis pubmed.ncbi.nlm.nih.gov
- Horm Res: pulsatile GnRH therapy in hypogonadotropic hypogonadism doi.org
- Drugs.com: gonadorelin (Factrel), discontinued in the US drugs.com