PT-141 (bremelanotide) is a synthetic cyclic heptapeptide and non-selective melanocortin receptor agonist (MC3R/MC4R) derived as an active metabolite of Melanotan II. It is FDA-approved (2019) for hypoactive sexual desire disorder (HSDD) in premenopausal women, marketed as Vyleesi. Unlike PDE5 inhibitors that target vascular blood flow, PT-141 acts on the brain's melanocortin system to increase libido and arousal, effective in both men and women through central nervous system pathways.
Category: Sexual Health. Evidence rating: A (strong human clinical data).
Clinical status: FDA-approved (Vyleesi for HSDD in premenopausal women)
PT-141 (MW ~1025 g/mol, C50H68N14O10, half-life 2-6 hours) is a synthetic analog of alpha-MSH targeting MC3R and MC4R. MC4R activation in the CNS enhances dopamine release in the nucleus accumbens and medial preoptic area, increasing sexual motivation. Subcutaneous bioavailability is approximately…
Research base: 6 registered clinical trials and 31 indexed publications reference PT-141.
Safety considerations: Common: nausea (~40%, most common and dose-limiting), flushing (50-70%), headache (10-25%), injection site reactions; Transient increases in blood pressure and heart rate; not recommended for uncontrolled hypertension or cardiovascular disease; Skin hyperpigmentation with repeated use (MC1R agonism); darker-skinned patients more susceptible; resolution not confirmed in all patients.
Reviewed by the PeptideAtlas Editorial Team. Last reviewed: 2026-08-12.
Related peptides: Bremelanotide.
Compare: PT-141 vs Bremelanotide.
PT-141 is the research name. Vyleesi is the FDA-approved brand (bremelanotide) for HSDD in premenopausal women at 1.75 mg SC, taken 45 minutes before anticipated activity.
Double-blind placebo-controlled studies showed significant improvements in erectile function with intranasal PT-141 in men with ED. However, it is not FDA-approved for men.
PT-141 works on the brain's melanocortin system to increase desire via dopamine release. Viagra works peripherally on blood flow via PDE5 inhibition. PT-141 targets desire; Viagra targets erectile mechanics.
Yes. Bremelanotide is the active metabolite of Melanotan II, isolated as the compound responsible for sexual arousal effects. It has a more targeted profile than MT-II.
The FDA labeling restricts use to 8 doses/month based on clinical trial protocols and to limit cumulative nausea burden and blood pressure effects.