PT-141 (Bremelanotide): The Melanocortin Peptide for Desire
PT-141 is a melanocortin agonist that acts centrally in the brain — the only approved peptide that targets desire rather than blood flow.
PT-141, also known as bremelanotide and marketed as Vyleesi, is a synthetic analog of alpha-melanocyte stimulating hormone (α-MSH). It activates MC3 and MC4 receptors in the hypothalamus to trigger sexual arousal — a fundamentally different mechanism than Viagra-class PDE5 inhibitors, which work on penile blood flow.
Mechanism
Melanocortin receptors in the hypothalamus modulate sexual desire in both sexes. PT-141 was originally developed as a tanning agent (it's a melanotan analog), but the desire effect was so reliable in trials that it was repurposed.
Dosing
Research doses range from 0.5 to 1.75 mg subcutaneously, taken 30–60 minutes before activity. Higher doses produce stronger effects but also more nausea and facial flushing.
Side Effects
Nausea is the dominant side effect — usually mild but real. Transient blood pressure increases, facial flushing, and a temporary darkening of moles (it's still a melanocortin agonist) are also reported.
Reference page
Reconstitution chart, dose calculator, and storage notes for this peptide.
Open the reference cardFAQ
- Is PT-141 the same as Viagra?
- No. Viagra increases blood flow; PT-141 increases desire. The two can be used together but address different aspects of sexual function.