Kisspeptin is a gnrh-upstream peptide. Gonadorelin is a gnrh peptide.
They are aimed at different things: Kisspeptin at libido & fertility; Gonadorelin at hormone / fertility.
| Comparison | Kisspeptin kisspeptin-10 · metastin | Gonadorelin (GnRH) GnRH · LHRH |
|---|---|---|
| How it works | How it works Kisspeptin sits at the very top of the reproductive hormone chain. Everything downstream depends on it, which is why a fault in it causes puberty not to start. | How it works 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. |
| What it is | A peptide that switches on natural sex-hormone signaling for libido and fertility. | A shot that keeps your own testosterone and fertility hormones going. |
| Status | Research only | In clinical usePrescription/compounded |
| Typical dose | — | 0.1–0.2 mg per dose |
| How often | As studied | 2-3x per week or more |
| Dose comes from | No established range | Clinical guideline |
| Cycled? | Should not be given continuously. Response fades within about two weeks of twice-daily dosing Published human study | Pulsed, not continuous. How often you give it decides whether it switches the system on or off Published human study |
| What it does | ||
| Drug class | GnRH-upstream peptide | GnRH peptide |
| Used for | A peptide that switches on the body's natural sex-hormone signaling, studied for libido, fertility, and hormone support, with a gentler feel than PT-141. | A shot that tells the body to make its own testosterone and fertility hormones, often used alongside testosterone therapy to keep the testicles working. |
| Receptors hit | — | — |
| Numbers | ||
| Full dose line | Varies (research) | 0.1 up to 0.2 mg per dose (start low, increase slowly) |
| Why that cycle | This one has real tolerance data and it points the opposite way from most peptides here. Twice-daily dosing in women caused the response to collapse inside two weeks, with luteinising hormone falling from 23.3 to 1.1 by day 14. Twice-weekly dosing held up far better. The pituitary itself stayed responsive, so the fade happens upstream in the hypothalamus. | 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. |
| Weight / effect | Not measured in a trial | Not measured in a trial |
| Chain length | 10 residues | 10 residues |
| Common vial | 5 mg | 10 mg |
| Before you start | ||
| Route | Under the skin (subcutaneous) | Under the skin (subcutaneous) |
| Do not use if | No formal contraindications established | Known allergy to gonadorelin Any condition where raising sex hormones would be unwise Pregnancy or breastfeeding |
What separates them
Proof behind the dose. Gonadorelin has a dose that follows clinical guidelines. Kisspeptin has no established dose range at all.
Legal standing. Gonadorelin is approved or in established clinical use. Kisspeptin is research-only, meaning no regulator has assessed it for use in people.
What doesn't differ: They are both taken the same way (under the skin). Neither has a measured effect size from a published trial, so there is no number to rank them on.
What people actually report
Kisspeptin
- Generally well tolerated in trials, but data is limited.
- Signs of an allergic reaction
Gonadorelin (GnRH)
- Mostly injection-site reactions.
- Because it clears fast, it needs frequent dosing.
- Swelling, trouble breathing, or hives, since repeated use has caused severe allergic reactions
Side effects are what users and trials report most often, not a complete list. Anything sudden, spreading, or breathing-related is an emergency regardless of which compound caused it.
People also compare
This comparison does not cover cost, long-term safety, or how you personally will respond. Effect figures come from separate trials in different populations and are not always directly comparable to each other. Nothing here is medical advice or a recommendation to use any of these. Talk to a clinician about your own situation.