Public Safety Warning References Only · Not Advice
FDA · TGA · WADA · peer-reviewed literature Updated May 2026 Reviewed by Allmeds AI Pharmacist

Melanotan II Side Effects: Why Regulators Warn Against It

Melanotan II is a synthetic analogue of alpha-melanocyte-stimulating hormone (alpha-MSH). It is marketed online for tanning and is sold by unlicensed sellers. It is not approved by any regulator. The UK Medicines and Healthcare products Regulatory Agency (MHRA), the Australian Therapeutic Goods Administration (TGA), and other agencies have warned the public against use. Reported adverse events include new and changing moles, melanoma case reports, priapism, and serious infections from non-sterile injection.

Melanotan II is not FDA-approved and lacks controlled human safety data. Not approved anywhere. UK MHRA has issued public warnings. TGA classifies it as an unlicensed and unsafe substance. Case reports describe melanoma diagnoses following melanotan II use. This page summarises the published literature and regulator positions. It is not medical advice.

Key Takeaways

  • Melanotan II is not approved anywhere in the world.
  • The UK MHRA and Australian TGA have issued public warnings against use.
  • Published case reports describe melanoma diagnoses, new and changing moles, priapism, and serious infections from non-sterile injection.
  • It is sold by unlicensed sellers; product purity and content are unknown.

What is Melanotan II, and what is it marketed for?

Melanotan II. Melanotan II is a non-selective melanocortin receptor agonist (binding MC1R through MC5R). It stimulates melanocyte activity, which increases skin pigmentation, but also affects sexual function, appetite, and other melanocortin-mediated processes.

What side effects and safety concerns have been reported?

The summary below draws from the published literature and regulator statements. Severity classification follows the source documents.

ConcernWhat has been reportedSource
New and changing moles, melanoma case reportsPublished case reports describe rapidly evolving naevi and melanomas after melanotan II useMHRA-cited concern
PriapismProlonged painful erection requiring emergency careMelanocortin-pathway adverse event
Nausea, vomiting, flushing, severe facial pigmentationCommon acute reactionsMHRA case-report literature
Serious infections from non-sterile injectionSepsis, abscess, infective endocarditis case reportsUnlicensed product sold via underground channels
Cardiovascular effectsTachycardia, hypertension, palpitations reportedCase reports
No regulator approval anywhereUnlicensed sale and useActive public-safety warnings

Taking Melanotan II alongside prescription medicines?

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Common Questions About Melanotan II

Is melanotan II legal?

Melanotan II is not approved as a medicine in any country. The UK Medicines and Healthcare products Regulatory Agency (MHRA) and Australian Therapeutic Goods Administration (TGA) have explicitly warned against its sale and use. Sale through unlicensed channels may be illegal depending on jurisdiction.

What are the main risks of melanotan II?

Reported risks include new and changing moles, melanoma case reports, priapism, severe nausea and vomiting, facial pigmentation, cardiovascular effects, and serious infections from non-sterile injection. These are documented in regulator warnings and peer-reviewed case reports.

Is melanotan II the same as melanotan I?

Melanotan I (afamelanotide) is a different molecule and is approved in some jurisdictions for erythropoietic protoporphyria under specialist supervision. Melanotan II is not approved anywhere. They should not be confused.

Should I check my moles if I have used melanotan II?

Speak to your doctor. Published case reports include melanomas diagnosed after melanotan II use. A clinical skin assessment is appropriate.

References

  1. UK Medicines and Healthcare products Regulatory Agency (MHRA). Melanotan: do not buy or use. Source.
  2. Therapeutic Goods Administration (Australia). Tanning injections containing melanotan. Source.
  3. Cardones AR, Grichnik JM. Alpha-melanocyte-stimulating hormone-induced eruptive naevi. Arch Dermatol. 2009;145(4):441-444. Source.
  4. Hjuler KF, Lorentzen HF. Melanoma associated with the use of melanotan-II. Dermatology. 2014;228:34-36. Source.
Not medical advice. This page summarises regulator statements and peer-reviewed literature for general education. It is not a substitute for professional medical advice, diagnosis, or treatment. Speak to your doctor or pharmacist before using any peptide.