Vyleesi is a melanocortin receptor agonist

Women with HSDD have an imbalance of neurotransmitter activity in the brain that impacts sexual desire: too few excitatory signals (such as dopamine or melanocortins) or too many inhibitory signals (such as serotonin) or a combination of both1,2

Excitatory signals: dopamine, norepinephrine, oxytocin, and melanocortins (MCs) and inhibitory signals: serotonin (5-HT), opioids, endocannabinoids.
Excitatory signals: dopamine, norepinephrine, oxytocin, and melanocortins (MCs) and inhibitory signals: serotonin (5-HT), opioids, endocannabinoids.

Vyleesi is a melanocortin receptor agonist that nonselectively activates several receptor subtypes, the most relevant of which are MC1R and MC4R.1

The exact mechanism by which Vyleesi improves HSDD in women is unknown.1