Gonadorelin
Synthetic gonadotropin releasing hormone (GnRH), a decapeptide. The only current human approval reached is a UK diagnostic vial; the pulsatile ovulation induction approval is now discontinued, and the popular use alongside testosterone therapy is off-label with no trial. Vietnam's largest pharmacy chain lists no gonadorelin product at all.
Last updated: September 2026
Category
Hormonal Support
Frequency
Single injection (test) or pulsatile pump (therapy)
Research
Approved diagnostic; pulsatile therapy trialsWhat is Gonadorelin?
Gonadorelin is synthetic gonadotropin releasing hormone (GnRH), also called luteinising hormone releasing hormone (LHRH). It is a decapeptide, ten amino acids in the sequence pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2, chemically identical to the hormone the hypothalamus releases to drive the pituitary (molecular formula C55H75N17O13, molecular weight about 1182). You can compare it with the other hormone axis compounds in our peptide library.
Its approved human use is narrow. The one current human label reached in this research is a UK diagnostic vial (Gonadorelin 100 micrograms, also branded HRF), authorised only to test pituitary function. In the United States both human products, Factrel and the Lutrepulse pump kit, are discontinued, and the only gonadorelin still on label there is veterinary. Canada shows the same pattern: every human product is cancelled or dormant while veterinary products stay marketed. Nearby in our library, kisspeptin acts one step upstream of GnRH, and enclomiphene raises testosterone by a different route.
The reason gonadorelin now appears in testosterone therapy discussions is off-label. Compounding pharmacies make it after the approved products went away, and after compounded hCG became harder to obtain, and some clinics prescribe it to keep the testicles stimulated during testosterone therapy. That use has no trial behind it: no study of gonadorelin given alongside testosterone was found, and the clinics that sell it concede it does not have the testicular evidence that hCG has. Everything below separates what the labels and trials establish from what is only community practice.
How It Works
Pituitary stimulation: the label mechanism is that gonadorelin stimulates the synthesis and release of follicle stimulating hormone (FSH) and luteinising hormone (LH) from the anterior lobe of the pituitary (UK diagnostic label).
Pulse dependence: the direction of the effect depends on how it is given. A single dose raises circulating gonadotropins and sex hormones, while continuous, non-pulsatile exposure downregulates the pituitary and eventually lowers sex hormone output. This is why therapeutic use is delivered in pulses by pump, not as a steady infusion (Vietnamese National Drug Formulary).
Upstream versus downstream: a TRT information site frames the contrast with hCG as gonadorelin acting at the pituitary (upstream) while hCG acts directly at the testes (downstream). This is recorded as a claim from a commercial page, not as a trial result.
Short half life: gonadorelin is rapidly hydrolysed in plasma. The UK label gives a half life of about 4 minutes, while the Canadian monograph gives a two phase figure of 2 to 10 minutes initial and 10 to 40 minutes terminal. Renal failure prolongs it; liver disease does not (UK SmPC; Ferring Lutrepulse monograph).
Benefits
- Diagnostic testing is the approved human use: a single 100 microgram injection produces a marked rise in LH and FSH used to assess pituitary gonadotrope function (UK diagnostic label; human study, 67 men, intravenous, PMID 33704441).
- Ovulation induction by pulsatile pump in women with hypothalamic amenorrhoea was the therapeutic indication on the Lutrepulse label (now discontinued in the US and Canada), and in the one registered randomised placebo controlled trial 5 of 9 women ovulated at 20 micrograms per pulse versus 0 of 10 on placebo (trial, 39 women, subcutaneous pump, NCT01976728).
- Spermatogenesis in men with congenital hypogonadotropic hypogonadism: pulsatile pump therapy raised FSH, LH and testosterone and produced sperm in 33 of 45 men in a retrospective cohort (retrospective study, 45 men, subcutaneous pump, PMID 39210488).
- Restored menstruation and natural pregnancies in women with idiopathic hypogonadotropic hypogonadism on pulsatile therapy, in a small series (retrospective study, 5 women, PMID 26813133).
- Compared with hCG in adolescent boys, pulsatile GnRH produced larger testes with no significant difference in side effects (comparative study, 12 boys on pump versus 22 on hCG, PMID 25978110).
- Higher bone mineral density after six months of pulsatile gonadorelin in young men with hypogonadotropic hypogonadism (study, 22 men, PMID 26417369).
Dosing Described in Research and Labels
| Phase | Dose | Frequency | Duration |
|---|---|---|---|
| Diagnostic test, adults (approved human label) | 100 micrograms (label dose, not a recommendation) | Single subcutaneous or intravenous injection | One test; samples at baseline then 15, 30, 45, 60 and 120 minutes (UK SmPC) |
| Diagnostic test, children from 1 year (Vietnamese formulary) | 2.5 micrograms per kg, maximum 100 micrograms (label dose, not a recommendation) | Single intravenous or subcutaneous injection | Vietnamese National Drug Formulary monograph |
| Ovulation induction, pulsatile (Lutrepulse label, now discontinued) | 5 to 20 micrograms per pulse (label dose, not a recommendation) | Subcutaneous pump, one pulse every 90 minutes, may change to 120 | Continued until follicle maturation and ovulation (Ferring Lutrepulse monograph) |
| Ovulation induction, randomised trial | 10, 15 or 20 micrograms per pulse (trial dose, not a recommendation) | Subcutaneous OmniPod pump, per pulse | Phase 3, 39 women, hypogonadotropic hypogonadism; 5 of 9 ovulated at 20 mcg vs 0 of 10 on placebo (NCT01976728) |
| Congenital hypogonadotropic hypogonadism, men | 7 to 15 micrograms per pulse (trial dose, not a recommendation) | One pulse every 90 minutes, subcutaneous pump | Retrospective, 45 men, mean 19.1 months; spermatogenesis in 33 of 45 (PMID 39210488) |
| Idiopathic hypogonadotropic hypogonadism, women | 10 micrograms per pulse (trial dose, not a recommendation) | One pulse every 90 minutes, pump | Retrospective, 5 women, at least 12 weeks (PMID 26813133) |
| Congenital hypogonadotropic hypogonadism, male infants | 5 micrograms per 90 minutes (trial dose, not a recommendation) | Subcutaneous pulsatile pump infusion | 7 infants, 3 to 5 months (PMID 40099791) |
| Veterinary label, cattle | 86 to 200 micrograms per cow (veterinary label, cattle, not for human use) | Single intramuscular or intravenous injection | Doses from the US FACTREL, CYSTORELIN, FERTAGYL and GONAbreed cattle labels; CYSTORELIN, FERTAGYL and GONAbreed state Not for use in humans |
| Alongside testosterone therapy (off-label, no trial) | 100 to 500 micrograms (community practice, no trial) | Subcutaneous, 2 to 3 times per week, as described by TRT clinics | No gonadorelin plus testosterone trial was found; the clinics that offer it call the use off-label |
These figures summarise what published research and approved labels describe. They are educational, not a recommendation or a personal protocol. Any dose, schedule, or decision to use a compound belongs with a licensed prescriber.
Side Effects
Common
- ⚠Injection site reactions such as induration, redness, itching or swelling, the local effect noted most across the labels (UK diagnostic label; Vietnamese formulary)
- ⚠Hot flushes, and in women heavier menstrual bleeding, listed as common in the Vietnamese formulary (Vietnamese National Drug Formulary)
- ⚠Breast tenderness, mood swings and nausea occurred more often on drug than placebo in the pulsatile ovulation trial (39 women, NCT01976728)
- ⚠Nausea, abdominal discomfort, headache and dizziness, listed as rare to uncommon on the UK diagnostic label (UK SmPC)
Rare
- •Hypersensitivity reactions including bronchospasm, tachycardia, urticaria and flushing, reported chiefly after repeated dosing (UK SmPC; withdrawn US Factrel insert)
- •Anaphylaxis: one paediatric case lost consciousness within 3 minutes of intravenous gonadorelin acetate and recovered after epinephrine (case report, PMID 26197466)
- •Antibody formation after chronic dosing, reported in about 3% of subcutaneous Factrel patients and sometimes tied to reduced effectiveness (Canadian Lutrepulse monograph)
- •Pituitary apoplexy: gonadorelin and its analogues are not recommended in pituitary adenoma because haemorrhagic infarction may occur; a case of apoplexy and sudden blindness has been reported (UK SmPC; withdrawn US Factrel insert)
- •Ovarian hyperstimulation (under 1%) and multiple pregnancy (12% of pregnancies) with pulsatile ovulation induction (Ferring Lutrepulse monograph)
- •Gynecomastia and subcutaneous induration in a pulsatile therapy cohort of men (8 and 6 of 45; PMID 39210488)
Who Should NOT Use Gonadorelin
- ✕Known or suspected pregnancy; it should not be given to pregnant women or nursing mothers (UK SmPC)
- ✕Hypersensitivity to gonadorelin or to any excipient in the product (UK SmPC; Canadian Lutrepulse monograph)
- ✕Pituitary adenoma: not recommended because pituitary apoplexy (haemorrhagic infarction) may occur (UK SmPC)
- ✕For pulsatile ovulation induction: ovarian cysts, or any condition that could be worsened by pregnancy such as a pituitary prolactinoma (Canadian Lutrepulse monograph)
- ✕Athletes subject to anti-doping testing: gonadorelin is prohibited at all times on the 2026 prohibited list (VADA 2026 list, which states it tracks the WADA 2026 list)
What to Expect
In the stimulation test, LH and FSH rise within about 15 to 60 minutes and are sampled out to 120 minutes; a single dose acts for roughly 3 to 5 hours (UK diagnostic label; Vietnamese formulary).
In hypogonadotropic hypogonadism, pulsatile pump therapy raised LH within about a week in one small series, and menstruation appeared at 35 to 55 days in most treated women (retrospective, 5 women, PMID 26813133).
Penile length increased over 3 to 5 months in male infants, and bone mineral density rose over 6 months in young men, in small hypogonadotropic hypogonadism studies (PMID 40099791; PMID 26417369).
Sperm appeared in most treated men with congenital hypogonadotropic hypogonadism over many months of pulsatile therapy (retrospective, 45 men, PMID 39210488), and in one comparative study the pump reached spermatogenesis earlier than cyclical gonadotropins, a median of 6 versus 14 months (comparative study, 28 men, PMID 30569789).
No trial has measured what to expect when gonadorelin is used with testosterone; the clinics that offer it say it does not have evidence comparable to hCG for preserving testicular function (off-label, no trial).
Notes from Ho Chi Minh City
In Ho Chi Minh City the gonadorelin you actually encounter is the diagnostic one, not a men's-health vial. Endocrinology units run the GnRH stimulation test to work up precocious puberty, and the compound has a full monograph in the national formulary with dosing text on pages 841 to 842. What you will not find is a box of it on a Long Chau shelf: a search of Vietnam's largest chain returns nothing for gonadorelin, while the GnRH agonist analogues in the same class, triptorelin as Diphereline and goserelin as Zoladex, are catalogued but were showing out of stock. The TRT-clinic framing that dominates the English search results is a different world from what a District 1 pharmacist can hand you, and the honest gap is that no trial has tested gonadorelin alongside testosterone at all. Dose, route, and whether to use it are decisions for a licensed clinician, not a self-administered protocol.
Sourcing in Vietnam
Gonadorelin is not stocked by Vietnam's retail pharmacy chains: a search of Long Chau, the largest chain, returns zero gonadorelin products, though it catalogues class analogues such as Diphereline (triptorelin) and Zoladex (goserelin), both shown out of stock. The compound has a national formulary monograph and the GnRH stimulation test is offered as a hospital service, but whether any gonadorelin product holds a Vietnamese marketing registration could not be established. In the US the entire registered supply is bulk powder for compounding rather than a finished drug; the FDA has issued a warning letter against a seller marketing gonadorelin as a research peptide and has logged three Class II recalls of compounded gonadorelin for sterility failures. No retail price is published, so treat any quoted figure as unverified and see the supplier list and COA guide before purchasing.
FAQ
Q: Is gonadorelin FDA approved?
A: It was. Gonadorelin was FDA approved as a diagnostic agent (Factrel) and for pulsatile ovulation induction (Lutrepulse), but both applications are now discontinued, so there is no current US human label and DailyMed returns zero human results. The UK still authorises a diagnostic vial. In the US the registered supply is bulk powder for compounding, and in June 2026 the FDA called gonadorelin sold as a research peptide an unapproved new drug. A commercial page that describes it as currently FDA approved is out of date.
Q: Gonadorelin or hCG during TRT, what does the evidence show?
A: They act at different levels: gonadorelin at the pituitary and hCG directly at the testes, a distinction drawn by a TRT information site rather than by a head to head trial. No trial of gonadorelin given alongside testosterone was found, and one clinic states plainly that gonadorelin does not have comparable evidence to hCG for maintaining intratesticular testosterone or semen parameters during testosterone therapy. For a different testosterone strategy discussed in our library, see enclomiphene.
Q: Can you buy gonadorelin in Vietnam?
A: Gonadorelin has a monograph in the Vietnamese National Drug Formulary, and Vietnam National Children's Hospital lists a GnRH stimulation test among its services, but Vietnam's largest retail chain, Long Châu, returns zero gonadorelin products while it does list class analogues such as Diphereline (triptorelin) and Zoladex (goserelin), both shown out of stock. The precocious puberty protocol and the hospital treatment page use GnRH agonist analogues rather than native gonadorelin. Whether any gonadorelin product holds a Vietnamese marketing registration could not be established, and no retail price is published. See the supplier list and the peptide library for context.
Q: Is gonadorelin banned in sport?
A: Yes. The 2026 prohibited list names gonadorelin under testosterone stimulating peptides and their releasing factors, prohibited at all times, and two peer reviewed papers note its misuse in doping and describe a validated urine test for it. Anyone subject to anti-doping testing should treat it as banned.
Where to Get Gonadorelin in Vietnam
See our community-verified supplier list with COA verification and cold-chain shipping to Vietnam.
Related Peptides
Related Guides
Research & Sources
- Gonadorelin 100 micrograms powder for solution for injection: Summary of Product Characteristics (SmPC) · electronic Medicines Compendium (emc), Datapharm · MA holder Esteve Pharmaceuticals Ltd (UK) (2022) Link
The only current human gonadorelin label reached; indication is purely diagnostic. Gives the 100 microgram adult dose, sampling schedule, contraindications and frequency-banded side effects. Text revised 30 August 2022.
- Product Monograph: Lutrepulse (Gonadorelin Acetate for Injection) 3.2 mg/vial · Ferring Inc. · Health Canada product monograph (2016) Link
Therapeutic (ovulation induction) human label giving the 5 to 20 microgram per pulse pump regimen; the corresponding Canadian DINs are now Dormant or Cancelled Post Market.
- Drugs@FDA records for active ingredient gonadorelin (Factrel; Lutrepulse Kit) · US Food and Drug Administration, openFDA · openFDA Drugs@FDA endpoint (2026) Link
Both US human applications returned marketing_status Discontinued; dataset last updated 2026-09-04.
- FACTREL (gonadorelin hydrochloride) injection, US label · Zoetis Inc. · DailyMed, US National Library of Medicine (2022) Link
Current US veterinary (cattle) label; states the decapeptide sequence and molecular weight 1182, the per-cow dose, and is categorised as a prescription animal drug label. NADA 139-237.
- Factrel (Gonadorelin): prescribing information, reproduction of the withdrawn US human package insert · RxList (secondary reproduction of the discontinued manufacturer insert) (n.d.) Link
Withdrawn US human diagnostic insert, distinct from the current veterinary FACTREL label above; source for the 100 microgram adult dose, the multiple-dose hypersensitivity wording, and the reported case of pituitary apoplexy with sudden blindness.
- Warning Letter: Wholesale Peptide (MARCS-CMS 729447) · US FDA, Center for Drug Evaluation and Research · FDA Warning Letters (2026) Link
FDA states gonadorelin sold as a research peptide is an unapproved new drug under section 505(a); dated June 17, 2026.
- openFDA drug enforcement (recall) records for gonadorelin · US FDA, openFDA · openFDA drug enforcement endpoint (2022) Link
Three Class II recalls of compounded gonadorelin (Tailor Made Compounding; APS Pharmacy) for lack of sterility assurance.
- Gonadorelin monograph, Vietnamese National Drug Formulary (Duoc thu Quoc gia Viet Nam, 3rd edition), reproduced · Bo Y te (issued under Decision 3445/QD-BYT) · trungtamthuoc.com reproduction, pages 841 to 842 (2022) Link
Secondary reproduction of the national formulary monograph; gives dose forms, the diagnostic and pulsatile dosing, half life and duration, and the adverse reaction list. A formulary monograph is not a marketing registration.
- Long Chau pharmacy on-site search for gonadorelin (zero results) · Nha thuoc Long Chau · Server-rendered search result (2026) Link
Returned totalCount 0 for gonadorelin while control queries (triptorelin, buserelin, hCG) returned non-zero counts; the chain lists class analogues, shown out of stock.
- Official Prohibited List 2026 (states it tracks the WADA 2026 list) · Voluntary Anti-Doping Association (VADA) · VADA Prohibited List ver. 1-1-2026 (2026) Link
Names gonadorelin under S2.2.1 testosterone-stimulating peptides, prohibited at all times. The WADA original could not be fetched (bot challenge).
- Phase 3 randomised placebo-controlled trial of subcutaneous pulsatile gonadorelin for ovulation induction (NCT01976728) · Ferring Pharmaceuticals · ClinicalTrials.gov (2018) Link
39 women with primary amenorrhea and hypogonadotropic hypogonadism; 10, 15 or 20 micrograms per pulse via pump versus placebo; ovulation 5 of 9 at 20 micrograms vs 0 of 10 placebo, pooled p 0.0120.
- [Effect and safety of pulsatile GnRH therapy for male congenital hypogonadotropic hypogonadism] · Zhonghua nan ke xue (National Journal of Andrology) (2024) (PMID: 39210488)
Retrospective, 45 men, gonadorelin 7 to 15 micrograms per pulse every 90 minutes; spermatogenesis in 33 of 45; adverse events included gynecomastia (8) and subcutaneous induration (6).
- [Effectiveness and safety of pulsatile GnRH pump therapy on female patients with IHH] · Zhonghua yi xue za zhi (2015) (PMID: 26813133)
5 women, 10 micrograms per 90 minutes for at least 12 weeks; LH rose from 2.2 to 5.4 U/L; menstruation in 4 of 5 at 35 to 55 days; two natural pregnancies.
- Efficacy and safety of pulsatile GnRH pump therapy in male infants with congenital hypogonadotropic hypogonadism · Endocrine Connections (2025) (PMID: 40099791)
7 male infants, 5 micrograms per 90 minutes for 3 to 5 months; penile length rose from 1.27 to 2.43 cm; no obvious adverse reactions reported.
- Pulsatile GnRH Is Superior to hCG in Therapeutic Efficacy in Adolescent Boys With Hypogonadotropic Hypogonadism · The Journal of Clinical Endocrinology and Metabolism (2015) (PMID: 25978110)
12 boys on 8 to 10 micrograms per 90 minutes via pump versus 22 on intramuscular hCG; larger testes with GnRH; no significant difference in side effects.
- The Pulsatile Gonadorelin Pump Induces Earlier Spermatogenesis Than Cyclical Gonadotropin Therapy in Congenital Hypogonadotropic Hypogonadism Men · American Journal of Men's Health (2019) (PMID: 30569789)
28 azoospermic CHH men, 10 on the pulsatile gonadorelin pump versus 18 on cyclical gonadotropin therapy; median time to spermatogenesis 6 months on the pump versus 14 months.
- Pituitary response to GnRH stimulation tests in different FSHB-211 G/T genotypes · Human Reproduction (2021) (PMID: 33704441)
Diagnostic use; 67 men given an intravenous bolus of 100 micrograms gonadorelin acetate; marked FSH and LH rise (P < 0.0001 for linear trend).
- Anaphylaxis to gonadorelin acetate in a girl with central precocious puberty · Journal of Pediatric Endocrinology & Metabolism (2015) (PMID: 26197466)
Case report; anaphylaxis within 3 minutes of intravenous gonadorelin acetate, treated with epinephrine, recovered within 30 minutes.
- Changes in Bone Mineral Density and Metabolic Parameters after Pulsatile Gonadorelin Treatment in Young Men with Hypogonadotropic Hypogonadism · International Journal of Endocrinology (2015) (PMID: 26417369)
22 young men; 6 months of pulsatile gonadorelin; bone mineral density increased at lumbar spine, femoral neck and total hip.
Important Disclaimer
Educational content only. Not medical advice. Peptides discussed on this page are not approved by Vietnam’s Ministry of Health (Bộ Y Tế) or the Drug Administration of Vietnam (DAV) for the indications described. Research peptides are not stocked at Long Châu, Pharmacity, or any retail pharmacy in Vietnam. Consult a licensed physician before any use.