FDA-approved for HSDD — acts on brain receptors, not vascular pathways.
PT-141 (bremelanotide) is a cyclic heptapeptide melanocortin receptor agonist. Unlike PDE5 inhibitors (Viagra, Cialis) which work via vascular mechanisms, PT-141 acts directly on melanocortin receptors in the brain and nervous system to increase sexual desire and arousal. It is FDA-approved as Vyleesi for HSDD (hypoactive sexual desire disorder) in premenopausal women.
Mechanism: PT-141 activates melanocortin-3 and melanocortin-4 receptors (MC3R/MC4R) in the hypothalamus and limbic system — brain regions regulating sexual behavior, appetite, and motivation. This central mechanism is fundamentally different from PDE5 inhibitors and can work even when vascular ED medications fail.
| Starting Dose | 0.5–0.75 mg | Assess tolerance — flushing, nausea common |
|---|---|---|
| Standard Dose | 1.0–1.75 mg | Most users' effective dose |
| Maximum | 2 mg | Do not exceed per use |
| Frequency | Max 2× per week | Not for daily use |
| Timing | 45–60 min before | SubQ abdomen or thigh |
Start at 0.5–0.75 mg to assess tolerance. Flushing and transient nausea are common at doses above 1 mg. The FDA-approved dose (Vyleesi) is 1.75 mg. Allow at least 45–60 minutes for onset. Maximum 2 uses per week. Not for daily use. Do not use with antidepressants that increase serotonin (risk of serotonin syndrome — consult prescriber).