Gonadorelin 2 mg vial dosage

What Gonadorelin is

Class:

Decapeptide - synthetic gonadotropin-releasing hormone (GnRH/LHRH)

Also called:

GnRH, LHRH, Gonadorelin acetate, Gonadorelin hydrochloride, Factrel, Lutrepulse

Used for:

FDA approved decades ago as a diagnostic test of pituitary function (Factrel) and as a pulsatile treatment for hypothalamic amenorrhea (Lutrepulse). Both approved products are discontinued. Today it is mainly sold through compounding pharmacies and research-peptide sellers to men on testosterone therapy, paired with TRT to keep the pituitary-testicular signal running - a use no trial has tested.

Human evidence:

Moderate human evidence. Real controlled human evidence exists, but it belongs to the approved, historical uses. The pivotal multicenter trial behind Lutrepulse's approval gave pulsatile intravenous gonadorelin acetate to 109 women with hypothalamic amenorrhea and reported ovulation in 91-96% of them. A 2021 study still used a 100-microgram intravenous bolus as a pituitary stimulation test in adult men. Chinese cohort studies report pulsatile subcutaneous-pump treatment inducing spermatogenesis in adult men with congenital hypogonadotropic hypogonadism. None of this evidence covers the popular current use - low-dose subcutaneous gonadorelin self-injected alongside testosterone therapy to preserve testicular size and fertility - for which I located no published human trial. See the dosing page for the studies themselves, cited.

Half-life:

About 2 to 10 minutes in humans; short enough that its effect depends on dosing pattern (single bolus vs. repeated pulses vs. continuous exposure), not just total dose.

US status:

Unapproved drug. Gonadorelin was FDA-approved twice: as gonadorelin hydrochloride (Factrel, NDA 018123, approved 30 September 1982) for diagnostic pituitary testing, and as gonadorelin acetate (Lutrepulse Kit, NDA 019687, approved 10 October 1989, orphan drug) for pulsatile treatment of primary hypothalamic amenorrhea. FDA's own Drugs@FDA record lists every strength of both as 'Discontinued' - the status FDA uses when a sponsor has stopped marketing a product, distinct from a safety-driven withdrawal - though I could not confirm this session whether FDA has issued the kind of formal 'not withdrawn for safety or effectiveness' finding it has issued for some other discontinued drugs. DailyMed's current gonadorelin listings (Cystorelin, Factrel, Fertagyl, Gonabreed, Ovacyst) are all veterinary products for livestock, unrelated to the discontinued human NDAs. No FDA-approved human gonadorelin product is on the market today; what is sold to consumers is compounded or otherwise unapproved. I could not confirm gonadorelin's current placement on FDA's interim 503A bulk-substance category list from a primary FDA document this session; an industry compounding-pharmacy education site (Fagron Academy, dated October 2023) states gonadorelin acetate was added to the separate 503B category-1 list, not 503A. Not evaluated in Australia's Poisons Standard, so I have not verified a scheduling status there.

The full picture, with every study: Gonadorelin guide.

How to mix a 2 mg Gonadorelin vial

For this vial: 1.5 mL of bacteriostatic water makes 1.33 mg/mL, so 75 mcg is 5.5 units (0.06 mL) on a U-100 insulin syringe. Pick a different volume from the units table if you want bigger or smaller draws; the number of doses stays the same.

1. Wipe the rubber stoppers of both the peptide vial and the bacteriostatic water vial with an alcohol swab and let the alcohol dry. ^[3][4]
2. With a new sterile needle and syringe, draw up the amount of bacteriostatic water you have chosen for the dilution. ^[3][4][5]
3. Inject the water into the peptide vial by aiming the stream against the inside glass wall, which helps prevent foaming. ^[6]
4. Swirl or roll the vial gently until the powder has fully dissolved; do not shake it. Do not inject the solution if it is cloudy or has particles in it. ^[3][4][6]
5. Label the vial with the date and time it was mixed, the amount of water added and how long it can be used after mixing. ^[3]
6. Store the mixed vial in the refrigerator at 2-8°C (36-46°F) and do not freeze it. ^[6]

Step by step with pictures: how to reconstitute peptides. About the water itself: bacteriostatic water.

Storing Gonadorelin vials

• Freeze-dried (lyophilized) peptide keeps far longer than peptide in solution; peptide suppliers advise storing the powder at -20°C away from bright light. ^[7]
• Protect peptide vials from heat and light. ^[7][8]
• Avoid repeated freeze-thaw cycles; a prescription peptide label also says not to freeze a vial once it has been mixed. ^[6][7]
• Once a multi-dose vial, such as bacteriostatic water, has been opened (needle-punctured), date it and discard it within 28 days unless its manufacturer states another date. ^[9][10]

More detail: peptide storage and shelf life.

Injecting safely

• Clean the injection site with an alcohol swab and let the skin dry completely before injecting. ^[11][12]
• Pinch up a fold of skin and fat (not muscle) and insert the needle at a 45- to 90-degree angle: 90 degrees where there is enough fatty tissue, 45 degrees where there is little. ^[11][12][13]
• Pulling back on the plunger (aspiration) is not necessary for a subcutaneous injection, because the chance of the needle being in a blood vessel is small. ^[11]
• Inject slowly, at roughly 10 seconds per mL. ^[11]
• Common sites are the belly, the thigh and the upper arm; rotate sites, keeping each injection at least 1 inch (2.5 cm) from the last. ^[6][11][12]

Hygiene and warning signs

• Use a new sterile needle and syringe for every injection and every time you enter a vial; never reuse them. ^[5][9][12]
• Never share needles, syringes or pens with anyone, even if the needle is changed; unsafe injection practices spread hepatitis B, hepatitis C and HIV. ^[5][8][9]
• Put used needles and syringes in a sharps disposal container straight away (FDA-cleared if possible), never loose in the trash, recycling or toilet, and dispose of the container following your community's guidelines. ^[14][15]
• Contact a health care provider if the injection site shows signs of infection, such as redness, swelling, red streaks or a fever. ^[12]

Where to inject: subcutaneous injection sites.

How Gonadorelin works

• Gonadorelin is a synthetic copy of gonadotropin-releasing hormone (GnRH, also called LHRH), the ten-amino-acid peptide the hypothalamus uses to signal the pituitary. It was sold as the acetate salt (Lutrepulse) for pulsatile treatment. ^[16][17]
• It acts on the pituitary to release LH and FSH. In a 2021 study, a single 100-microgram intravenous dose of gonadorelin acetate produced a marked rise in both hormones in 67 men tested for secondary hypogonadism. ^[18]
• The pattern of delivery decides the effect. In rhesus monkeys with hypothalamic lesions, hourly pulses of GnRH restored gonadotropin secretion, but a constant infusion did not and could switch the response off (desensitisation). ^[16]
• It is cleared fast: in 6 volunteers given intravenous LHRH, the plasma half-life was 2.4 minutes (plus or minus 0.4). ^[19]

What the Gonadorelin research found

Human evidence: moderate human evidence. Each result says what was studied.

• Human studyIn a multicentre trial of Lutrepulse, pulsatile intravenous gonadorelin acetate led to ovulation in 91% of women with primary hypothalamic amenorrhoea and 96% with secondary hypothalamic amenorrhoea (109 women in total). ^[17]
• Human studyIn a 2019 non-randomised study of 28 azoospermic men with congenital hypogonadotropic hypogonadism, a subcutaneous gonadorelin pump (10 men) produced sperm sooner than cyclical hCG/hMG (18 men): a median of 6 against 14 months. Final success rates were not significantly different (90% against 83.3%). ^[20]
• Human studyIn a 2019 study of 220 men with hypogonadotropic hypogonadism, pulsatile subcutaneous GnRH produced sperm in 62 men and combined hCG/hMG injections in 26, reported as 53% against 25%, though the paper's group sizes do not match these percentages. Sperm first appeared after an average of 6.2 months with GnRH against 10.9 months with hCG/hMG. ^[21]
• Human studyA 1995 meta-analysis of hormone treatment for undescended testes (3,282 boys) found LHRH worked in 21% of cases in randomised trials, against 4% with placebo. ^[22]
• Human studyIn a 2025 study of 7 male infants with congenital hypogonadotropic hypogonadism, 3 to 5 months of pump-delivered gonadorelin increased penile length, testicular volume, inhibin B and anti-Mullerian hormone. No obvious adverse reactions were recorded. ^[23]

Gonadorelin side effects and risks

No current drug label is cited here; these side effects come from clinical studies, a case report and animal work, none of them in men self-injecting alongside testosterone therapy.

• Human studyA 1989 case report describes a woman on long-term pump-delivered gonadorelin (Factrel) who developed wheal-and-flare skin reactions at the injection sites. Skin-prick testing was positive and IgE antibodies to the hormone were found, though one antibody test (RAST) was negative; the authors concluded it was an IgE-mediated allergy. ^[24]
• Human studyIn a 2019 study of men using a subcutaneous gonadorelin pump, allergic skin redness with hardening was a common side effect. ^[20]
• Human studyThe Lutrepulse trial reported a 12% incidence of multiple pregnancy. There was one case of ovarian hyperstimulation, in a woman also taking clomiphene citrate. ^[17]
• Human studyComplications of the intravenous line used for pulsatile delivery ranged from 0% to 11% across the Lutrepulse trial centres (mean 7%). ^[17]
• Animal studyIn monkeys, a constant infusion rather than pulses failed to sustain gonadotropin release and could desensitise the pituitary, the opposite of the intended effect. ^[16]

Other things to know

• No FDA-approved product exists today for any use, so there is no FDA-reviewed dosing, contraindication or monitoring guidance for the self-injected, TRT-adjacent use it is now mostly sold for.
• A published case report documents an IgE-mediated hypersensitivity reaction - skin wheal-and-flare at injection sites, confirmed by skin-prick testing - after long-term pump-delivered gonadorelin (Factrel) treatment in one patient.
• Continuous or excessively frequent dosing desensitises the pituitary GnRH receptor and can suppress, not stimulate, the LH/FSH axis - the opposite of the intended effect - so dosing pattern matters as much as dose size.
• A vial sold outside the discontinued, formally approved supply chain carries no FDA-verified content, purity or actual concentration.

Reported side effects and what the studies measured: Gonadorelin side effects.

Where this vial size comes from

Gonadorelin is sold as a 2 mg vial by the pages below, each checked on the date shown. I list them as evidence that this size exists, not as a recommendation to buy from them.

• SwissChemsvendorLists it as: Gonadorelin 2mg · checked 2026-09-28
• Beyond ResearchvendorLists it as: Gonadorelin (2 mg.) $ 39.99 · checked 2026-09-28
• Peptide WarehousevendorLists it as: Available In 2MG · checked 2026-09-28

The doses come from the sourced common protocol on the Gonadorelin dosing page, and every number on this page is arithmetic on those doses and this vial size.

Other Gonadorelin vial sizes

• 2 mg
• 5 mg vial

Questions

How much water do I add to a 2 mg Gonadorelin vial?

There is no single correct amount: water changes how many units a dose is, not how many doses the vial holds. With 1.5 mL the vial is 1.33 mg/mL and 75 mcg is 5.5 units (0.06 mL) on a U-100 insulin syringe. The units table gives 1.5, 3, 5 mL.

How many doses are in a 2 mg Gonadorelin vial?

40 doses at 50 mcg, 26 doses at 75 mcg, 20 doses at 100 mcg.

How long does a 2 mg Gonadorelin vial last?

At 75 mcg a dose and 2-3 times weekly, about 8.7-13 weeks. How long a mixed vial keeps is a separate limit; see storage below.

How many 2 mg vials do I need for a 4-week run?

1 vial at 50 mcg 2 times a week for 4 weeks; 1 vial at 100 mcg 3 times a week for 4 weeks.

What does 1 unit equal in a 2 mg Gonadorelin vial?

13.33 mcg with 1.5 mL, 6.67 mcg with 3 mL, 4 mcg with 5 mL of bacteriostatic water, on a U-100 syringe.