PT-141 (Bremelanotide) is a melanocortin receptor agonist FDA-approved as Vyleesi for hypoactive sexual desire disorder in premenopausal women. Research protocols use subcutaneous injection 45–60 minutes before the observation period.
Standard Research Dosage
1–2 mg subcutaneously, administered 45–60 minutes before the research observation period. FDA-approved Vyleesi uses 1.75 mg. Start at 1 mg to assess tolerability; escalate to 1.75–2 mg if well tolerated.
Mechanism of Action
PT-141 activates MC4R in the hypothalamus and limbic system, producing central nervous system-mediated sexual arousal. Unlike PDE5 inhibitors (sildenafil), PT-141 acts on the CNS rather than the peripheral vasculature.
Side Effect Management
Nausea (40% of subjects at 1.75 mg in clinical trials) is the primary side effect. Taking an anti-nausea medication 30 minutes before injection significantly reduces nausea incidence. Flushing and headache are also common but transient.