Gonadorelin (GnRH)_
Also known as GnRH, LHRH, Factrel
A shot that keeps your own testosterone and fertility hormones going.
Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.
What is Gonadorelin (GnRH)?
Plain language first. The technical label stays, but it never stands alone.Overview
Gonadorelin is synthetic GnRH, the hormone your brain uses to tell the pituitary to make testosterone and fertility hormones. In plain terms: it prompts your own hormone production, often used alongside testosterone therapy to keep the testicles active. Because it clears fast, it needs frequent dosing.
What it's used for
A shot that tells the body to make its own testosterone and fertility hormones, often used alongside testosterone therapy to keep the testicles working.
How does Gonadorelin (GnRH) work?
What it does in the body, and where.Gonadorelin is GnRH itself, identical to what your brain releases. How you give it determines whether it switches the system on or shuts it off.
- 01It prompts the pituitary to release LH and FSHWhich in turn drive testosterone and sperm, or the ovarian cycle.
- 02Pulsed dosing stimulates, continuous dosing suppressesThe pituitary desensitises to a constant signal. This is not a side effect but the basis of an entire drug class used to shut hormone production down deliberately.
- 03Timing therefore matters more than doseWhich is why it is given as frequent small injections rather than a steady level.
- 04It clears in minutesA very short half-life, which is what makes pulsed dosing practical.
Where this compound is thought to act.
What else is it used for?
Each use below carries its own evidence level. Approved means regulators have cleared it for that purpose. Investigational means it is in trials. Early research means it is being studied and is not established.
- Testing whether the pituitary gland is working, which was its approved diagnostic useClinical use
- Keeping the testicles working during testosterone therapy, which is the main reason it is used nowClinical use
How much, and do you cycle it?
The range, and whether you take breaks.0.1 up to 0.2 mg per dose (start low, increase slowly), 2-3x per week or more. Pulsed, not continuous. How often you give it decides whether it switches the system on or offHuman study
This is the clearest cycling story in the whole set. Given in pulses roughly every one to two hours it stimulates the axis; given continuously it shuts the axis down. That is not a side effect, it is the mechanism, and it is what drugs like leuprolide exploit to suppress testosterone deliberately. Continuous dosing does the opposite of what most people taking it want.
Source: Belchetz et al., pulsatile vs continuous GnRH (Science 1978)
How do I dose and price it?
Enter your vial and your dose. Pick a mix. We show the draw and the cost.The vial holds a fixed amount of drug. Adding more water does not make more drug, it just spreads it thinner, so you draw a bigger number on the syringe for the same dose.
Choose your mix
Measuring the water1 mL = one full 100-unit syringe.
Your draw
2 / 100 unitsHow do you store it?
Before mixing, and after.Dry powder in the freezer or fridge. Once mixed, fridge, and use within about a month.
Unmixed lyophilized Gonadorelin (GnRH) keeps for a long time cold. Once you add water the clock starts: most reconstituted vials hold up for roughly 28 to 30 days at fridge temperature. Keep it out of light, and do not freeze it after mixing.
What are the side effects and cautions?
Known cautions and warnings for this compound.Who should avoid it
- Known allergy to gonadorelin
- Any condition where raising sex hormones would be unwise
- Pregnancy or breastfeeding
Stop and get help
- Swelling, trouble breathing, or hives, since repeated use has caused severe allergic reactions
Common effects
- Headache and light-headedness
- Nausea
- Injection-site reactions
- Generally mild after a single dose
Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.
Is Gonadorelin (GnRH) approved?
And where the numbers on this page come from.Yes. Approved for clinical use.
A regulator has cleared it for specific uses in a clinical setting.
- DoseFrom product labeling and clinical guidelines.
- Vial sizeFrom what vendors typically list; not a recommendation.
- Reviewed22 July 2026
What else is like Gonadorelin (GnRH)?
Others in Sexual and hormonal, side by side.If you're weighing Gonadorelin (GnRH), it's worth reading PT-141 (Bremelanotide), Kisspeptin, and HCG (Human Chorionic Gonadotropin) in the same class.
A shot that keeps your own testosterone and fertility hormones going.
- Dose
- 0.1 up to 0.2 mg per dose (start low, increase slowly)
- How often
- 2-3x per week or more
An approved shot that boosts sexual desire through the brain.
- Dose
- 1.75 mg per dose
- How often
- As needed, before activity
A peptide that switches on natural sex-hormone signaling for libido and fertility.
- Dose
- Varies (research)
- How often
- As studied
A hormone shot that keeps the testicles making testosterone and sperm.
- Dose
- 250 up to 500 IU per dose (alongside testosterone therapy)
- How often
- 2-3x per week
10What these words mean
Show glossary +
What these words mean
- Titrate
- Starting at a low dose and increasing it slowly over time so your body adjusts and side effects stay mild.
- Subcutaneous
- An injection just under the skin, into the fat layer, usually with a short, thin insulin needle.
- Intramuscular (IM)
- An injection into a muscle, using a longer needle.
- Reconstitution
- Mixing a powdered peptide with liquid (bacteriostatic water) so it can be drawn into a syringe.
- Bacteriostatic water
- Sterile water with a tiny amount of preservative, used to mix powdered peptides.
- Concentration
- How strong the mixed peptide is, in milligrams per milliliter (mg/mL). More water makes it weaker; less water makes it stronger.
- Units (on the syringe)
- The marks on an insulin syringe. 100 units equals 1 mL. They measure how much liquid you draw, not the dose in milligrams.
- mcg and mg
- Units of dose. 1 milligram (mg) equals 1,000 micrograms (mcg).
- GLP-1
- A natural gut hormone that lowers appetite and blood sugar. Drugs that copy it, like semaglutide, are used for weight loss.
- Growth hormone secretagogue
- A compound that nudges your body to release more of its own growth hormone, rather than injecting the hormone itself.
- Half-life
- How long a compound stays active in your body. A longer half-life means you inject less often.
- Peptide vs small molecule
- A peptide is a short chain of amino acids. A few items here (like MK-677 or methylene blue) are small molecules, not true peptides, but people use them the same way.
- Research only
- No approved dose or use in people. Sold for research and not reviewed by the FDA for safety or quality.
- Investigational
- Still being tested in clinical trials and not yet approved or legally sold for general use.
- Banned in drug-tested sport
- Prohibited by the World Anti-Doping Agency (WADA); using it can disqualify a competing athlete.
Last reviewed 22 July 2026