ED / HSDD / low libido

Bremelanotide (PT-141), a melanocortin-4 receptor agonist, is FDA-approved for premenopausal HSDD and in RCTs significantly increases sexual desire and reduces desire-related distress; it also augments erectile response when combined with sildenafil in men.

Kisspeptin administration modulates sexual and limbic brain processing and increases penile tumescence and desire measures in men with HSDD in randomized placebo-controlled crossover trials, marking it an emerging pharmacological target for low sexual desire.

Oxytocin shows early human evidence for improving sexual function: a randomized trial of vaginal oxytocin gel improved desire, arousal, lubrication, and overall sexual function in postmenopausal women, with a case report of broad sexual benefit from intranasal oxytocin in a man.

Melanotan II, a non-selective melanocortin receptor agonist, activates central pro-erectile and pro-arousal pathways and was the developmental precursor to bremelanotide, but evidence for sexual dysfunction remains largely mechanistic and early-clinical rather than definitive.

Tadalafil, a long-acting PDE5 inhibitor targeting the vascular arousal pathway, is an established first-line ED treatment with efficacy comparable to sildenafil and greater patient/partner preference in meta-analysis of RCTs.