Melanocortin receptor agonist — the only FDA-approved peptide for sexual arousal, marketed as Vyleesi.
PT-141 (bremelanotide) is a melanocortin-4 receptor agonist originally developed as a tanning agent before its pro-sexual effects were noticed. It's FDA-approved as Vyleesi for premenopausal hypoactive sexual desire disorder in women and is used widely off-label for both sexes as an on-demand libido and arousal peptide.
Unlike PDE5 inhibitors (Viagra, Cialis), PT-141 works centrally on arousal circuits in the brain rather than on peripheral vascular mechanics. This makes it useful when the issue is desire rather than erectile mechanics, and it can work in situations where Viagra doesn't.
It's a short-cycle, on-demand compound rather than a continuous protocol. Track BP (mild transient elevation common), nausea tolerance, and self-reported efficacy.
PT-141 activates the melanocortin-4 receptor (MC4R) in the hypothalamus, stimulating central pro-sexual signaling independent of vascular effects. Downstream it increases dopamine release in the medial preoptic area, which is the classical arousal circuit.
1–2 mg SC injected 45–90 minutes before anticipated sexual activity. Effects last 2–8 hours. Common side effects: flushing, transient BP elevation, nausea (dose-dependent). Not for daily use — spacing ≥3 days apart is typical. Start at 0.5–1 mg to assess tolerance.
Education only — not medical advice. Any protocol change should involve your licensed provider.
When running PT-141, these are the biomarkers most commonly tracked to assess response and safety:
Free calculator for PT-141 reconstitution math — vial size, BAC water volume, and exact syringe units.
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