Kisspeptin
aka Kisspeptin-10, KP-10, metastin
GnRH axis regulator
Half-life
~30 minutes (rapid)
How long it stays active in your body
Dosing
Single injection or pulsatile per protocol
How often you take a dose
Route
SubQ · IV
How it goes into the body
Status
Investigational
Still in clinical trials, not on the market
What it is
A peptide hormone that sits upstream of GnRH (gonadotropin-releasing hormone) — the master switch for the entire HPG axis. Activates GnRH neurons in the hypothalamus, which then stimulate LH/FSH from the pituitary, which then drives testosterone (men) and ovulation (women).
How it works
Binds KISS1R on GnRH neurons, triggering pulsatile GnRH release. Restores natural hormone pulsatility that suppressive protocols (long-term SARMs, anabolic cycles) disrupt. Bachmeyer's top recommendation for hormone axis reset.
What the research says
Multiple human trials for fertility and hypothalamic amenorrhea. Increasingly used in PCT protocols. Cost is the main barrier — research-grade typically $150 per injection in microdose protocols.
Sources: PubMed: Kisspeptin
Common dosing ranges
- Range
- 0.5–10 mcg/kg (research range varies widely)
- Frequency
- Single injection or pulsatile per protocol
- Duration
- Targeted use during HPG reset / PCT
Sources: PubMed
Administration
Side effects
Common
- Generally well-tolerated at research doses
- Transient facial flushing
Serious / theoretical
- Long-term safety in healthy users not established
- Avoid in pregnancy
Sources: PubMed
Notes
Bachmeyer's top recommendation for HPG axis reset. Different from HCG — HCG mimics LH downstream; kisspeptin activates the whole axis upstream. Pairs with HCG for full TRT restart protocols.