What It Is
Melanotan II is a synthetic cyclic melanocortin peptide that activates several melanocortin receptors. It is promoted online as a tanning injection or nasal spray, but it is not an FDA-approved drug and is not interchangeable with approved afamelanotide or bremelanotide products.[1][4]
What Small Human Studies Found
A 1996 phase 1 experiment enrolled only three healthy men. It reported increased pigmentation in two participants, along with nausea, fatigue or somnolence, yawning, and spontaneous erections lasting one to five hours at some exposures.[1] A later small placebo-controlled crossover study reported erectile responses in men with psychogenic erectile dysfunction.[2]
These small, decades-old studies demonstrate biological activity, not a modern safety profile, approved tanning product, or established treatment. They do not justify consumer dosing or claims of protection from ultraviolet radiation.
Safety Signals
FDA's current compounding-risk page cites published case reports of melanoma, posterior reversible encephalopathy syndrome, sympathomimetic toxidrome, and priapism, while also identifying aggregation, impurity, and immunogenicity concerns.[3] A case report cannot by itself prove causation, but these serious signals matter because no adequate regulated safety program establishes the risks or their frequency.
Australia's TGA warns of headache, nausea, vomiting, appetite loss, facial redness, increased moles or freckles, kidney dysfunction, and brain swelling reports, and states that unapproved online products may be counterfeit or poor quality.[5] A prolonged erection is an emergency; new or changing pigmented lesions require clinical assessment.
Tanning Does Not Equal Sun Protection
A pigment change induced by Melanotan II does not provide the protection of an appropriate sunscreen and does not make ultraviolet exposure safe. The TGA explicitly warns that no artificial or natural tan prevents sun damage.[5]
Regulatory Status
FDA has treated Melanotan II sold as an injectable tanning product as an unapproved new drug and pursued enforcement against unlawful distribution.[4] The TGA states that melanotan tanning products are unapproved in Australia and have not been assessed there for quality or safety.[5]
Approval of Vyleesi (bremelanotide) or Scenesse (afamelanotide) for narrow, product-specific indications does not validate Melanotan II.[6][7]