Melanocortin receptor agonists, penile erection, and sexual motivation: Human studies with Melanotan II

H. Wessells, N. Levine, M. E. Hadley, R. Dorr, V. Hruby

Research output: Contribution to journalArticle

87 Scopus citations


We review our experience with Melanotan II, a non-selective melanocortin receptor agonist, in human subjects with erectile dysfunction (ED). Melanotan II was administered to 20 men with psychogenic and organic ED using a double-blind placebo-controlled crossover design. Penile rigidity was monitored for 6 h using RigiScan. Level of sexual desire and side effects were reported with a questionnaire.In the absence of sexual stimulation, Melanotan II led to penile erection in 17 of 20 men. Subjects experienced a mean of 41 min Rigiscan tip rigidity>80%. Increased sexual desire was reported after 13/19 (68%) doses of Melanotan II vs 4/21 (19%) of placebo (P<0.01). Nausea and yawning were frequently reported side effects due to Melanotan II; at a dose of 0.025 mg/kg, 12.9% of subjects had severe nausea. We conclude that Melanotan II is a potent initiator of penile erection in men with erectile dysfunction. Our findings warrant further investigation of melanocortin agonists and antagonists on penile erection.

Original languageEnglish (US)
Pages (from-to)S74-S79
JournalInternational Journal of Impotence Research
StatePublished - Oct 1 2000



  • Impotence
  • MSH
  • Penile erection
  • Sex behavior

ASJC Scopus subject areas

  • Urology

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