Kisspeptin-5
Also called kisspeptin fragment
Kisspeptin is the master switch at the very top of the reproductive hormone chain: it tells the hypothalamus to release GnRH, which tells the pituitary, which tells the gonads.
Studied in people, in small numbers.
- Hormone balance
- Sexual health
The quick answer
Kisspeptin is the master switch at the very top of the reproductive hormone chain: it tells the hypothalamus to release GnRH, which tells the pituitary, which tells the gonads. Kisspeptin-5 is one of several natural fragments of that signal. The one people actually use and discuss is Kisspeptin-10.
What it is not
Not testosterone replacement - it works upstream through your own axis, which is a different thing entirely.
Why people use it
🔑 Sits above the whole chain rather than replacing anything downstream; ⚖️ Works through your own loop, so the feedback system stays intact; 🔬 An active area of human research
What people report using
No settled community convention exists for it yet, and we would rather say that than invent a range. If you have seen one reported, the conversation is the place to tell us.
What to expect, and when
Not well characterised for this fragment. See Kisspeptin-10.
Side effects, and what people do about them
Very little is reported specifically, largely because very little is used. The Kisspeptin-10 reports are mild - some flushing, an occasional headache.
Go deeper
Open these only if you want them.
How it actually works
A short fragment of kisspeptin-54 acting at the KISS1R (GPR54) receptor to drive GnRH release. The fragments differ mainly in stability and potency, and the ten-amino-acid fragment is the one carried into human research.
More on the evidence
No established dosing convention exists for this in people. The work behind it is animal and cell research, and human use is sporadic enough that no consistent pattern has formed in community reporting either. We are not publishing a ladder because there is not one to publish — this is the "nobody knows yet" case rather than the "we have not got to it" case. If you have seen numbers circulating, bring them to us before you draw anything up.
What people report, in full
This is a case where the honest answer is that the community is talking about something else. Search kisspeptin and you get Kisspeptin-10: the reports, the conventions, the timing advice and the stacking discussion all attach to that fragment. Kisspeptin-5 appears on supplier lists, but there is very little first-hand experience attached to it, and the people writing about it are usually reasoning by analogy from the -10 material rather than from use. That is worth saying plainly instead of dressing up a thin record. If you are researching this family, the Kisspeptin-10 entry is where the actual body of reports lives.
Worth knowing
The trials are real. They were not asking the question most people are asking when they come looking for this one.
Human research on kisspeptin has been genuinely productive, but nearly all of it used kisspeptin-10 or kisspeptin-54, not the -5 fragment.
Sources and review
This record is built on what the wider community reports doing and experiencing, summarised above. No counted dataset has been attached to this compound yet — when one is published, it goes here with its numbers.
Everything above was written from the research and community reporting behind this compound, but we have not found a primary paper we are willing to put our name to. We would rather tell you that than point you at something we have not read.
Last reviewed 2026-09-08.
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Still not sure?
Ask it the way you would ask a person. Follow-up questions are the point — it remembers what you already said.
Ask about Kisspeptin-5