Melanocortin receptor agonist · FDA-approved (Vyleesi, 2019)
An FDA-approved, as-needed injection that acts on brain melanocortin pathways to raise sexual desire in certain premenopausal women, with real but modest effect sizes.
✦ 2 min read · 2 sourcesWhat it is
Bremelanotide (brand name Vyleesi, marketed as PT-141 in research/compounded settings) is a synthetic melanocortin-receptor agonist peptide. The FDA approved it in June 2019 for acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women, taken as needed by subcutaneous injection. It is not approved for postmenopausal women or for men.
How it works
Rather than acting on blood flow like erectile-dysfunction drugs, bremelanotide works centrally, activating melanocortin-4 (and related) receptors in brain regions involved in sexual motivation. The intended result is increased subjective sexual desire and reduced distress about low desire, not a mechanical arousal effect.
What the evidence shows
Approval rested on two identical 24-week phase 3 randomized, placebo-controlled trials (the RECONNECT studies, ~1,200 premenopausal women with HSDD). Both met their coprimary endpoints, improving the Female Sexual Function Index desire domain and reducing desire-related distress, but the effect sizes were modest (Cohen's d roughly 0.27–0.39). Nausea was the most common adverse effect and a frequent reason for discontinuation, and the data do not establish benefit outside the studied premenopausal HSDD population.
Quick check
Four questions, ~60 seconds, with a sourced result.
The honest take
The only women's-health peptide here approved by the FDA for a specific sexual-desire diagnosis, with modest but statistically significant trial effects.
Status & safety
Vyleesi is a prescription drug in the U.S. for the approved indication; legitimate access is through a licensed prescriber. Labeled cautions include transient blood-pressure increase (so it is contraindicated in uncontrolled hypertension or cardiovascular disease), nausea, and possible focal skin/gum darkening with repeated use. Compounded or research-sourced PT-141 outside the FDA-approved product is not quality-assured.
Summaries of published, third-party research for educational purposes. Not medical advice; not a claim of efficacy or safety for any use.
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