Bremelanotide is a synthetic analog of α-melanocyte-stimulating hormone that acts as a non-selective melanocortin receptor agonist, predominantly targeting MC3R and MC4R[3]. In the central nervous system, MC4R activation enhances dopamine release in key brain reward and arousal regions including the nucleus accumbens and medial preoptic area, which increases sexual motivation and desire[3]. Unlike PDE5 inhibitors, bremelanotide does not directly affect the nitric oxide pathway; in men, its erectogenic effect is secondary to this central mechanism stimulating nitric oxide production in penile tissue[3]. Peripheral MC1R agonism accounts for side effects such as transient blood pressure elevation and skin hyperpigmentation (tanning)[3][5].
