Melanotan II
MT-2 · MT2 · Melanotan 2
The tanning injection that also boosts libido and suppresses appetite. Popular, effective, and controversial.
Educational content only. Not medical advice. This compound may be regulated in your jurisdiction. Consult a healthcare professional.
01 What is Melanotan II?
Melanotan II is probably the most widely-used research peptide in the world, despite never being approved anywhere. Originally developed at the University of Arizona as a potential skin cancer prevention tool (the logic: if you can tan without UV exposure, you reduce melanoma risk), it took on a life of its own when users discovered it also dramatically increased libido and suppressed appetite. The tanning effect is real and dramatic. MT-2 stimulates melanocytes to produce melanin regardless of sun exposure, giving people with fair skin the ability to develop a deep tan with minimal UV. For many users, this is the primary appeal — a year-round tan without the skin damage of sunbeds or excessive sun exposure. But MT-2 is not without controversy. The unregulated market is massive, quality control is essentially non-existent in most cases, and the side effect profile is not trivial. Moles can darken (concerning for melanoma monitoring), nausea is common initially, and the compound's effects on multiple melanocortin receptors mean it is doing more to your body than just changing skin colour.
02 How Does It Work?
Melanotan II is a non-selective melanocortin receptor agonist — it activates MC1R (skin pigmentation), MC3R (energy homeostasis, sexual function), MC4R (appetite suppression, sexual arousal), and MC5R (exocrine gland function). The broad receptor profile explains its multiple effects. MC1R activation drives melanogenesis — melanocytes ramp up melanin production, darkening skin. MC4R activation suppresses appetite and increases sexual arousal (this is why PT-141, which selectively targets MC4R, was developed from MT-2). The multi-receptor activation means you get a package deal: tan, libido boost, and appetite suppression.
03 What Does The Research Say?
Moderate evidence. Some human data, mostly animal studies.
Developed through clinical trials at University of Arizona. Phase I/II studies confirmed: significant melanogenesis (tanning) with subcutaneous injection, increased sexual arousal (which led to PT-141 development), and appetite suppression. The tanning effect was robust and statistically significant. However, development was discontinued for the broad compound due to its non-selective receptor profile and side effects. The sexual dysfunction aspect was refined into PT-141. Concerns exist around: melanoma risk (theoretical — stimulating melanocytes in someone with existing atypical moles), cardiovascular effects of chronic melanocortin activation, and unmonitored mole changes.
04 Reported Dosages
Research literature dosages only. NOT medical recommendations. Always consult a healthcare professional.
Research protocols: Loading phase of 0.25-0.5mg subcutaneously daily for 2-4 weeks, then maintenance of 0.5mg once or twice weekly. Some users start lower (0.1mg) to assess nausea tolerance. Results typically visible within 1-2 weeks. These are community-reported dosages, not medical recommendations.
05 Side Effects & Risks
Nausea (very common initially, usually subsides), facial flushing, fatigue, darkening of existing moles (important for skin checks), spontaneous erections in men, mild appetite suppression. More concerning: potential for new mole formation, theoretical melanoma concerns, cardiovascular effects with chronic use.
06 Legal Status
Not approved. Actively warned against by MHRA. Available online as research chemical.
Not FDA-approved. FDA has issued warnings. Research chemical.
Not approved. Warned against by multiple health agencies.
Not approved. TGA has issued strong warnings.
Goal Guides for Melanotan II
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