What has been published on Melanotan II, and why it is case reports rather than trials

Melanotan II is a synthetic analogue of alpha-melanocyte-stimulating hormone. It shares a family with Melanotan I but not its history: that one became an approved medicine and this one did not.

The shape of the evidence, before its content

This is the first thing to understand and it structures everything else.

Of the compounds in this catalogue with human literature, almost all have it in the form of a trial: people assigned at random, a comparison group, an endpoint decided in advance. For Melanotan II, what exists are case reports: specific patients who turned up at a clinic and whose doctor published what they saw.

A case report cannot establish a risk or a cause. It serves a different purpose: raising a hand.

What those cases describe

A 2017 review collected what has been published on the unregulated use of these analogues [1]:

• Cutaneous complications, in particular melanocytic changes in existing moles and the appearance of new naevi, some dysplastic.
• Four published cases of melanoma arising from pre-existing moles during melanotan use or shortly after. The individual cases are described in the dermatological literature [2][3][4].
• Multiple national health organisations have issued warnings about the use of melanotan I and II [1].

And the other half, told just the same. That same review states expressly that conclusive evidence is lacking linking use with the appearance of those melanomas [1]. Four cases are not a series, and people who use these compounds are part of a tanning culture that on its own already means more sun exposure. Overstating the risk would make this page as unreliable as staying silent about it.

The other problems the review points to

Beyond the dermatological, the paper points to questions of preparation, administration and dose in a product nobody regulates [1]. Put another way: part of the uncertainty is not about the molecule but about what a given vial actually contains.

What does not exist

There is no marketing authorisation for Melanotan II from any agency. The only analogue of this hormone with a European authorisation is afamelanotide, which is a different molecule, in implant form and for a rare disease [5].

This page describes published literature. It is not medical information, it does not describe a therapeutic use, and it does not replace any healthcare professional. Any change in a mole — size, border, colour, bleeding — is a reason to see a dermatologist.

What to look at when comparing suppliers

• Batch identity confirmation, which matters doubly here: Melanotan I and II are constantly confused and are different molecules.
• HPLC purity for the specific batch, with a certificate you can read before buying.
• Be wary of anyone citing afamelanotide data to talk about this product. They are different molecules and one of them never went through an agency.