Bremelanotide (research context)
Evidence Grade C — Moderate human evidence. 20 published studies, 17 human. 0 registered clinical trials.
PT-141 is the research designation for bremelanotide, which is sold as the prescription medication Vyleesi for low sexual desire in premenopausal women. This entry covers its unregulated use beyond the prescribed indication. Self-administration outside of medical supervision bypasses the blood pressure monitoring and dosing limits built into the approved product.
20 published studies: 17 human, 2 animal, 0 in-vitro, 5 reviews
PT-141 is the same molecule as bremelanotide, which is approved as Vyleesi (#40) exclusively for hypoactive sexual desire disorder in premenopausal women. Vyleesi is administered as a subcutaneous autoinjector under prescription.
PT-141 is available through unregulated channels for off-label purposes. Self-administration outside of prescribed use bypasses the medical evaluation that the approved product requires. The approved prescribing information includes a blood pressure monitoring requirement and limits use to one dose per 24 hours due to transient blood pressure increases. Products from unregulated sources lack pharmaceutical quality assurance and the dosing controls built into the approved delivery system.
PT-141 activates the MC4R melanocortin receptor in the hypothalamus, modulating dopaminergic pathways involved in sexual desire and arousal. This central brain mechanism is fundamentally different from PDE5 inhibitors (such as sildenafil), which act on blood vessels. The mechanism is established from the approved product's regulatory dossier.
Research suggests two large Phase III trials (1,267 participants total) established bremelanotide's efficacy for the approved indication (HSDD in premenopausal women), though effect sizes are modest. Small-scale off-label use data in men suggest effects on erectile function and desire, but no Phase III male data exist. The approved prescribing information includes dosing limits (one dose per 24 hours, eight per month) and blood pressure monitoring requirements. Unregulated use bypasses these safeguards. Nausea affects 40% of users. Potential skin darkening with repeated use may be permanent. Products from unregulated sources lack the dosing controls and quality assurance of the approved autoinjector.
No trials registered on ClinicalTrials.gov for this compound.
FDA ORIG 1
FDA SUPPL 2
The information on this page is provided for educational and research reference purposes only. This is not medical advice. Always consult a qualified healthcare professional before making any health-related decisions.
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