Machine-assisted translation — the German original version is authoritative.
Melanocortin System
Melanotan II
MT-II · MT-2
Melanotan II is an unapproved synthetic analogue of α-melanocyte-stimulating hormone (α-MSH). It broadly activates various melanocortin receptors and leads to skin tanning with little or no UV light. Precisely this nonspecific action explains the side-effect profile: documented are, among others, the rapid darkening and growth of moles, melanoma case reports, priapism (painful persistent erection), and nausea. Authorities in the United Kingdom, Australia, and other countries warn expressly against it.
Regulatory status
Not approved for humans
Not approved as a medicine anywhere; regulatory warnings due to melanoma and other risks.
Drug class
Unapproved α-MSH analogue (broad melanocortin agonist)
Half-life (informative)
Described as being in the range of hours.
Studied in the literature
In case reports and investigations subcutaneously; distribution is unregulated.
Mechanism of action
Melanotan II activates the MC1R (pigmentation/melanogenesis) as well as MC3R and MC4R (including sexual function, appetite). This results in tanning, but also erectile effects up to priapism, as well as nausea. The strong MC1R stimulation causes existing moles to darken.
Not a quality-controlled product — the composition varies.
Research history
Developed at the University of Arizona from α-MSH research; never approved as a medicine. Distributed over the internet as a "tanning injection" or nasal spray.
Regulatory status by region
The UK's MHRA warns expressly against unlicensed melanotan II.
The TGA has warned of the risks.
No approval; distribution unregulated.
Research areas
- Historically: photoprotection/tanning and erectile function
- Largely abandoned in favor of more targeted successors (afamelanotide, bremelanotide)
Documented effects (from the literature)
- Skin tanning; darkening and growth of moles.
- Nausea/vomiting, flushing, decreased appetite.
- Priapism; hyperpigmentation of the lips and gums.
Safety concerns & caution
- Melanoma case reports under melanotan II; rapid melanocytic changes make early detection of skin cancer more difficult.
- Priapism is a urological emergency.
- Systemic toxicity and rhabdomyolysis have been described.
Risks of gray-market purchase
- Non-sterile, with untested content.
- "Tanning without the sun" trivializes a product with no approval whatsoever.
- Altered moles can mask a melanoma.
Frequently asked questions
Is melanotan II a safe alternative to the tanning salon?
No. It is not approved, and there are case reports of melanomas as well as of priapism and systemic toxicity. New or changing moles under melanotan II should be evaluated by a dermatologist.
How does melanotan II differ from PT-141 or afamelanotide?
PT-141 (bremelanotide) and afamelanotide are more targeted and approved in certain countries. Melanotan II is the nonspecific, unapproved precursor.
Sources
Primary and reference sources for your own reading.
Related substances
Unfamiliar terms? Look them up in the glossary or read the fundamentals.
This profile is for information and education only. It is not medical advice and deliberately contains no dosing or usage details. Decisions about use belong in a doctor’s hands.