Melanotan II

What is Melanotan II?

Melanotan II is an unapproved non-selective melanocortin peptide that can darken skin, suppress appetite, and produce sexual-response effects, but the same receptor breadth creates a serious safety problem. Melanotan II activates several melanocortin receptors, including MC1R for pigmentation and central pathways tied to appetite and libido. Melanotan II earns a low score because early human efficacy signals are small and verified case reports include PRES, rhabdomyolysis, renal infarction, melanoma, and dysplastic-nevus proliferation.

From the BioHarmony report, reviewed 2026-09-20.

How it is thought to work

Non-selective melanocortin receptor activation

Safety watch-outs

• New or rapidly changing mole, oral pigmentation, or bleeding lesion
• Severe headache, confusion, vision change, chest pain, or neurologic symptoms
• Priapism, severe abdominal pain, dark urine, or muscle pain after dosing

Full risk profile in the BioHarmony report.

Dosing as published

No approved-label or study protocol is recorded for Melanotan II yet.

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