Compound profile
Melanotan II
Also known as MT-II
Last reviewed October 2026
Educational only. A summary of published research, not medical advice or a recommendation. No doses are listed.
Quick take
A synthetic analogue of α-melanocyte-stimulating hormone, sold illegally as a tanning product.
- Class
- Melanocortin peptides
- Status
- Not approved
- Evidence
- Early or small human studies
- Half-life
- Not well documented
Mechanism fingerprint
What it acts on, and how. Each chip links to that pathway on the map.
Activates several melanocortin receptors, darkening skin pigment and also affecting appetite and sexual function.
What makes it different
Activates melanocortin receptors broadly rather than one subtype, so it affects skin color, appetite and sexual function together.
Compare side by side
Mechanism & pathways
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Agonist
Melanocortin receptors
nonselective, including MC1R on pigment cells and MC4R in the brain
A family of five receptors. MC1R on pigment cells controls skin color; MC3R and MC4R in the brain affect appetite, energy use and sexual function.
Evidence overview
Early or small human studies
Small early human studies from the 1990s. It has no approved use.
A breakdown into human, animal and cell studies hasn't been added for this compound yet.
Why it's used
Used to tan without sun exposure, and sometimes for libido.
Side effects & risks
Reported side effects
- Nausea
- Facial flushing
- Spontaneous erections
- Reduced appetite
Risks and warnings
- New or darkening moles; case reports of melanoma
- Rare reports of serious kidney problems and priapism
- Products sold as “research use only” are not quality-controlled medicines; purity, sterility and labeled amount are not verified.
FAQ
Short answers taken from this profile.
What is Melanotan II?
A synthetic analogue of α-melanocyte-stimulating hormone, sold illegally as a tanning product.
How does Melanotan II work?
Activates several melanocortin receptors, darkening skin pigment and also affecting appetite and sexual function.
What receptors or pathways does Melanotan II act on?
melanocortin receptors (agonist; nonselective, including MC1R on pigment cells and MC4R in the brain).
How is Melanotan II different from similar compounds?
Activates melanocortin receptors broadly rather than one subtype, so it affects skin color, appetite and sexual function together.
Is Melanotan II approved?
Not approved anywhere. Health regulators in several countries have warned against it.
What has Melanotan II been studied for?
Used to tan without sun exposure, and sometimes for libido.
How strong is the evidence?
Early or small human studies. Small early human studies from the 1990s. It has no approved use.
What are the main risks?
New or darkening moles; case reports of melanoma. Rare reports of serious kidney problems and priapism. Products sold as “research use only” are not quality-controlled medicines; purity, sterility and labeled amount are not verified.
Sources
- Habbema L et al. Risks of unregulated use of alpha-melanocyte-stimulating hormone analogues: a review. Int J Dermatol 2017.
- Olney JJ et al. The protective effects of the melanocortin receptor (MCR) agonist, melanotan-II (MTII), against binge-like ethanol drinking are facilitated by deletion of the MC3 receptor in mice. Neuropeptides 2014.