Kisspeptin

Kisspeptin is a naturally occurring hormone that triggers the brain to release GnRH, driving the reproductive hormone axis. It is an investigational research peptide studied mainly for fertility and reproductive disorders — it is not an FDA-approved drug, and it has not been proven safe or effective for general use. This page is purely educational and is not medical advice; any decision about kisspeptin belongs with a licensed clinician.

Important: Most published human work on kisspeptin comes from controlled hospital and clinical-trial settings, not from at-home use. "Research use only" material sold online is not an approved medicine and is not a substitute for supervised care.

What is Kisspeptin?#

Kisspeptin is a family of signaling peptides produced from the KISS1 gene. The gene was originally identified in 1996 as a suppressor of cancer metastasis (hence the early name metastin), and only later was its central role in reproduction recognized. The peptides act through the KISS1R receptor, also known as GPR54.

Kisspeptin-10 (KP-10), also called metastin (45–54), is the short, 10-amino-acid fragment that retains the peptide's biological activity and is the form most commonly used in research. Longer fragments such as kisspeptin-54 also exist and behave somewhat differently — for example, kisspeptin-54 has a longer reported half-life than kisspeptin-10.

How does Kisspeptin work?#

Kisspeptin sits at the top of the body's reproductive hormone system, the hypothalamic-pituitary-gonadal (HPG) axis:

• Kisspeptin binds the KISS1R (GPR54) receptor on GnRH neurons in the hypothalamus.
• This prompts those neurons to release GnRH (gonadotropin-releasing hormone) in pulses.
• GnRH signals the pituitary gland to release LH and FSH.
• LH and FSH then act on the ovaries or testes to drive sex-hormone production and gametogenesis.

Because kisspeptin acts upstream of GnRH, it is often described as a key part of the "GnRH pulse generator." Research also suggests kisspeptin helps relay information about the body's energy stores to the reproductive axis, which is one reason it is of interest in conditions linked to negative energy balance.

What is Kisspeptin studied for?#

Most human research treats kisspeptin as a physiological tool and a potential therapy for reproductive conditions. It is not an approved treatment for any of these.

Reported effects in well-controlled studies have been generally encouraging for stimulating reproductive hormones, but the evidence base is early, sample sizes are often small, and no regulatory body has approved kisspeptin as a therapy.

Is Kisspeptin legal and FDA-approved?#

Kisspeptin is not FDA-approved for any indication. It is an investigational research peptide. It has been administered to people under research authorizations in clinical-trial and hospital settings, including registered trials on ClinicalTrials.gov, but that is different from being an approved drug you can be prescribed for routine care.

In 2024, an FDA advisory committee (the Pharmacy Compounding Advisory Committee) reviewed whether kisspeptin-10 should be added to the 503A bulks list (which would allow certain pharmacy compounding), in the context of treating secondary hypogonadism in men. The FDA proposed not adding it, citing that the peptide is not well characterized physicochemically, that there is limited information on immunogenicity risk, and that there is insufficient evidence of effectiveness (and that FDA-approved alternatives already exist). Material sold "for research use only" has not been evaluated by the FDA for safety, purity, or effectiveness, and its quality cannot be assumed.

Nothing here is legal advice; regulations vary by country and change over time. Check the rules in your jurisdiction.

How is Kisspeptin dosed in research?#

There is no validated, approved human dose of kisspeptin, and WikiPeps does not publish dosing protocols or amounts for any peptide. Published studies have used various forms (such as kisspeptin-10 and kisspeptin-54) and various routes and schedules under direct medical supervision, but those research conditions do not translate into a safe at-home regimen.

Dosing is a medical decision. If you are considering kisspeptin for any reason, that conversation should happen with a licensed clinician who can evaluate your individual health, monitor you, and weigh the risks.

How is Kisspeptin reconstituted?#

Kisspeptin is typically supplied as a lyophilized (freeze-dried) powder that must be reconstituted with a sterile diluent before it can go into solution. A general, education-only overview of how lyophilized peptides are handled is included in this page's "how-to" data, covering sterile technique, gentle mixing, and storage.

That overview is educational only and does not tell anyone how much to use or instruct self-administration.

What are the safety considerations?#

In the controlled human studies conducted so far, kisspeptin has generally been reported as well tolerated, without major safety signals in those settings. That is reassuring but limited: the studies are typically short, small, and run under medical supervision.

Key cautions:

• Long-term and repeated-use safety is not established. Most data are from single or short-course administration.
• It acts on a central hormone system (the HPG axis). Altering reproductive hormone signaling can have effects that are not obvious without monitoring, and is especially inappropriate without oversight in pregnancy, hormone-sensitive conditions, or fertility treatment.
• Unregulated "research" material is an unknown. Purity, identity, dose accuracy, and sterility are not guaranteed, which introduces risks beyond the peptide itself.
• Drug and condition interactions have not been well mapped outside trials.

Tell a clinician about any peptide you are considering, and seek prompt medical care for unexpected symptoms.

The bottom line#

Kisspeptin (KP-10, metastin) is a naturally occurring hormone that sits at the very top of the reproductive hormone axis, triggering GnRH release and the downstream LH/FSH cascade. It is a genuinely interesting subject of reproductive-medicine research — studied for fertility, hypothalamic amenorrhea, and sexual desire — but it is investigational and not FDA-approved, its human half-life is extremely short, and its long-term safety is unproven. There is no validated human dose, and WikiPeps does not provide one. Treat anything you read online as background for an informed conversation with a licensed clinician, not as medical advice.