Peptides›Other›Melanotan II

Melanotan II

/ Synthetic cyclic heptapeptide analog of alpha-MSH; broad melanocortin receptor agonist

TIER 3 · PreclinicalN = 0 · TESTING PENDINGLAST REVIEW 2026·04·20

ALIAS · MT-II · MT-2

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Research use onlyAny dose figures below describe what specific cited studies used, reported factually. Nothing on this page is guidance for human use.READ FIRST →

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§ A · Identity

Primary sequence— sequence not captured —

MW · —CLASS · Synthetic cyclic heptapeptide analog of alpha-MSH; broad melanocortin receptor agonistCATEGORY · Other

Parent compound of bremelanotide. No FDA approval. Historical academic work; subsequently developed into the approved derivative bremelanotide.

§ B · Mechanism of action

Melanotan II is a synthetic alpha-MSH analog that non-selectively activates melanocortin receptors (MC1R, MC3R, MC4R, MC5R). Activation of MC1R drives eumelanin production (sunless tanning) and activation of MC3R/MC4R influences sexual arousal and appetite pathways.

§ C · Human clinical evidence

Academic human work exists (e.g., Wessells 2000 erectile dysfunction study). Not approved as a therapeutic. The derivative bremelanotide was developed to achieve FDA approval with a narrower receptor profile.

§ D · Primary literature

PubMed10602369Wessells H et al. — Synthetic melanotropic peptide initiates erections in men with psychogenic erectile dysfunction: double-blind, placebo controlled crossover study · Journal of Urology · human-phase-2Double-blind crossover study reported Melanotan II induced erections in men with psychogenic erectile dysfunction.Limitations: Small study; historical work — later derivative bremelanotide (PT-141) was developed toward FDA approval for HSDD in women.2000

§ F · Safety signal

Adverse events reported include nausea, flushing, spontaneous erections, blood pressure changes, and focal hyperpigmentation with prolonged use. Reports of melanoma associated with unregulated Melanotan II use exist in the dermatology literature but causality is not established.

§ H · Regulatory status

Regulatory status

FDA status:: Not FDA-approved

§ I · Notable gaps and controversies

Heavily used in the unregulated research-chemical market for “tanning” purposes with no long-term human safety data at recreational doses. Dermatology case reports link unregulated use to melanocytic lesion changes without establishing causation.