PT-141
Bremelanotide · Vyleesi
PT-141 (bremelanotide) is a synthetic melanocortin receptor agonist and the first centrally acting peptide approved by the FDA for a sexual dysfunction indication — marketed as Vyleesi (Palatin Technologies / AMAG Pharmaceuticals) for hypoactive sexual desire disorder (HSDD) in premenopausal women. Unlike phosphodiesterase-5 inhibitors such as sildenafil, which act peripherally through vascular smooth muscle relaxation, PT-141 acts centrally via melanocortin MC3R and MC4R receptors in the hypothalamus to modulate sexual motivation and arousal pathways — a mechanistically distinct approach that is effective regardless of vascular status. Pivotal Phase 3 RCTs in premenopausal women with HSDD demonstrated statistically significant improvements in satisfying sexual events and desire scores versus placebo, establishing the clinical evidence base for FDA approval in 2019. PT-141 dosage: the FDA-approved dose is 1.75mg administered as a single subcutaneous injection in the abdomen using an auto-injector device, approximately 45 minutes before anticipated sexual activity; it should not be used more than once per 24 hours or more than 8 times per month per prescribing guidance. Compounded PT-141 — available through licensed compounding pharmacies — is commonly prepared in 10mg vials for research contexts; typical compounded doses range from 1–2mg per use. PT-141 nasal spray formulations have been investigated as an alternative delivery route, though the approved form is subcutaneous injection. PT-141 for men: while FDA approval is limited to premenopausal women with HSDD, PT-141 is used off-label in men for sexual dysfunction, including cases where PDE5 inhibitors are insufficient or contraindicated; the central mechanism of action is not sex-specific. Side effects: the most common adverse effect is nausea (reported in approximately 40% of subjects in pivotal trials), followed by flushing, headache, and transient hyperpigmentation with repeated use. A transient increase in blood pressure is observed in the first hour post-injection; PT-141 is contraindicated in patients with uncontrolled hypertension or cardiovascular disease. PT-141 (Vyleesi) is FDA-approved and requires a prescription; compounding pharmacy access also requires a prescription. Providers offering PT-141 consultations — including telehealth platforms — can be found in the PeptideBase directory.