KISS1-derived kisspeptin peptides: Kisspeptin-54 (Metastin) and Kisspeptin-10 (Metastin 45-54, YNWNSFGLRF-NH2)
Access and compounding status raise extra safety and legal questions.
A natural brain signaling peptide that triggers the release of reproductive hormones -- studies in people show it rapidly raises the hormones that control fertility and sex hormone production. It is not FDA-approved and is not available through regular pharmacies due to limited safety data.
This entry is a cited research summary, not an established treatment reference. Dosing language is included as source context, not as medical instruction.
The clearest reproducible human tolerability issue is tachyphylaxis: twice-daily SC kisspeptin-54 leads to marked desensitization of LH/FSH response within 2 weeks in women with hypothalamic amenorrhea (PMID 19820030), mitigated by less frequent dosing (twice weekly maintained response over 8 weeks; PMID 26194072). Acute symptomatic safety reporting is limited in the filtered paper set. One 30-participant study in males reported no significant blood pressure change (PMID 30046307). Review literature notes kisspeptin has been 'well-tolerated' with no serious adverse effects across multiple trials (PMID 24615662, PMID 26194072). However, FDA has identified potential significant safety risks including immunogenicity and peptide impurity concerns for compounded kisspeptin-10, and notes limited human safety data overall. In chronic animal studies, prolonged kisspeptin-54 administration (50 nmol/day SC for 13 days) caused testicular weight reduction and seminiferous tubule degeneration in rats via HPG axis desensitization (PMID 35837314). Flushing and injection site reactions reported in clinical research context but not well-characterized in the filtered study set.
If real-world use or exposure is being considered, review potential interactions, contraindications, and monitoring needs with a licensed clinician rather than relying on summary copy alone.
Sources: [1-18]