# Kisspeptin Dosage in Research: Doses, Routes, and Half-Life

> Kisspeptin dosage as studied in research: the bolus and infusion doses used in human trials by population and route, the kisspeptin-10 versus kisspeptin-54 half-life, nasal spray data, and tachyphylaxis.

Strictly what was administered, to which population, by which route — never a recommendation.

## Read this first

There is no standard human dose of kisspeptin, because it is not an approved medicine. Every number below is a research protocol — what scientists gave to volunteers or patients in a monitored study — and it is written here only to describe the literature, never as a how-to. No self-administration is implied.

Two facts shape kisspeptin dosing more than the amount does. First, the half-life: kisspeptin-10 (KP-10) is cleared in about 4 minutes, while the longer kisspeptin-54 (KP-54) lasts about 27 minutes — so the two isoforms behave very differently. Second, desensitization: give kisspeptin constantly or in big repeated doses and the receptor stops listening within days, so the response fades. That is why researchers care about timing and spacing, not just dose size. Routes studied include intravenous bolus, continuous infusion, under-the-skin injection, and — newly — a nasal spray. The studied doses, route by route, follow.

## Kisspeptin dosage

Across the human literature, kisspeptin dosage has been explored by population and route. In healthy men, kisspeptin-10 was given as a 0.3 to 1.0 microgram/kg intravenous bolus and as a 1.5 microgram/kg/h continuous infusion [3]. In women with hypothalamic amenorrhea, kisspeptin-54 was infused intravenously at 0.01 to 1.00 nmol/kg/h [5]. As an IVF egg-maturation trigger, kisspeptin-54 was given as a single subcutaneous bolus of 3.2 to 12.8 nmol/kg, with about 9.6 nmol/kg optimal [6]. In the sexual-brain and related studies, kisspeptin-54 was infused intravenously at roughly 1 nmol/kg/h [8]. Each figure is study-attributed: a dose studied at X, in a stated population, by a stated route. None is a dose for a person to take.

## Kisspeptin half life

The kisspeptin half life differs sharply between the two main isoforms, and it is the single most practical pharmacokinetic fact about the peptide. Kisspeptin-10 (KP-10) has a functional half-life of roughly 4 minutes in humans, cleared quickly by plasma peptidases [3]. Kisspeptin-54 (KP-54) is larger and more resistant to those enzymes, giving it a substantially longer half-life of about 27 to 28 minutes. That difference is why KP-54 is favored where a longer, steadier action is wanted (such as the IVF trigger), while KP-10's short half-life means receptor sensitivity may be better preserved with well-spaced or pulsatile exposure than with a constant drip.

## Kisspeptin nasal spray

A kisspeptin nasal spray is the newest delivery route and the most relevant to anyone hoping for a non-invasive option. In a 2025 study, intranasal kisspeptin-54 (primary dose 12.8 nmol/kg) rapidly stimulated LH release in healthy men, healthy women, and women with hypothalamic amenorrhea, with no adverse events, and the nasal-spray formulation stayed stable for up to 60 days at 4°C [16]. It was the first clinical demonstration that kisspeptin can be delivered effectively through the nose rather than by needle. It remains an investigational research formulation, not an approved or marketed nasal-spray product.

## The schedule problem: tachyphylaxis

The reason dosing schedule dominates this discussion is tachyphylaxis — the receptor desensitizing with sustained activation. Twice-daily subcutaneous kisspeptin-54 in women with hypothalamic amenorrhea caused the acute LH increment to fall from about 24 IU/L on day one to roughly 2.5 IU/L by the fourteenth injection day [12]. High-dose continuous intravenous infusion likewise showed desensitization during the infusion [5]. The honest takeaway across the literature: increasing dose or duration does not reliably increase or sustain the hormonal response and may blunt it, and the short half-life of KP-10 means well-spaced or pulsatile exposure preserves the signal better than continuous exposure. No human dosing schedule is recommended here — this is a description of what the studies found.

---

A field-notebook reading of the kisspeptin literature — the upstream-of-GnRH pulse it sets watched closely and recorded plainly, its sexual-brain findings kept apart from what people merely report; a place where the record is kept, never a clinic, a vendor, or a prescription.