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melanotan ii · tanning injection · fda

MT2 peptide (melanotan II)

MT2 is melanotan II, a synthetic seven-amino-acid copy of part of the hormone α-MSH that has never been FDA-approved. The FDA's safety notes cite published cases of melanoma, a brain-swelling syndrome (PRES) and priapism, and an FDA import alert targets melanotan sold as a "research" chemical.

Open Peptide Calculator editorial teamUpdated 18 sources

Never approvedMelanotan II has no FDA approval.[1] FDA: "Published case reports discuss serious adverse events including melanoma, posterior reversible encephalopathy syndrome, sympathomimetic toxidrome and priapism."[2] This page has no calculator.

What is the MT2 peptide?

MT2 is a ring-shaped (cyclic) seven-amino-acid analog of α-melanocyte-stimulating hormone, the signal that darkens skin.[18][8]

Structure
Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2[18]
Formula and weight
C50H69N15O9, 1,024.2 g/mol
Names
Melanotan II, MT-II, MT2

MT2 is not PT-141 or Scenesse

Two approved drugs are related to MT2, but they are different molecules with different, narrow approvals.

Melanotan II and its approved relatives
Melanotan II (MT2)Bremelanotide (PT-141)Afamelanotide (Melanotan-I)
FDA statusNever approvedApproved as Vyleesi, 2019[15]Approved as Scenesse implant, 2019[16]
Approved useNoneLow sexual desire in premenopausal womenLight sensitivity in erythropoietic protoporphyria
FormSold online as powder1.75 mg autoinjector16 mg implant

A 2012 toxicology report described bremelanotide as "a variation of Melanotan II".[12] The PT-141 page covers the approved drug.

FDA and regulator actions

MT2 has been treated as an unapproved new drug by the FDA since at least 2007, and it is on the FDA's list of compounding substances with safety concerns.

  • Compounding. In 503A Category 2 from September 2023; now in FDA's "nominated but withdrawn" safety table with the wording quoted above.[2] A 2020 letter listed it as ineligible for compounding.[4]
  • Under review again. Melanotan II is one of five bulk substances on the agenda of an FDA advisory committee meeting due before the end of February 2027, alongside cathelicidin LL-37 and GHK-Cu. The date is not set and no Federal Register notice had appeared by November 14, 2026.[3]
  • Imports. Import Alert 66-41 covers melanotan, noting products "imported as non-human research purposes only and then the unapproved new drug is sold on internet".[5]
  • Prosecution. After a 2007 FDA warning, one seller kept shipping melanotan II; its owner later pleaded guilty and was debarred by the FDA in 2016.[6]
  • United Kingdom. The MHRA says it has "repeatedly taken action to remove melanotan products ... from sale for over 10 years".[7]
  • Sport. Not named on the WADA 2026 list; its S0 class covers substances with no current approval for human use.[17]

What the human studies found

Three small studies from the University of Arizona in 1996–2000 are the human trial record; none studied tanning safety over the long term.

Published human studies of melanotan II
StudyPeopleAmount and route studiedReported
Dorr 1996[8]3 healthy men, pilot0.01–0.03 mg/kg under the skinDarker skin in 2; spontaneous erections; nausea, sleepiness and yawning
Wessells 1998[9]10 men with psychogenic erectile dysfunction0.025 mg/kg under the skin, crossover vs placeboErections in 8 of 10; nausea, yawning, reduced appetite
Wessells 2000[10]10 men with organic erectile dysfunction0.025 mg/kg under the skinErections after 12 of 19 injections vs 1 of 21 on placebo; severe nausea after 4 of 19

A phase 2 trial combining MT2 with light therapy for vitiligo was registered in 2026, with no results yet.[14]

Reported harms

Case reports link MT2 to skin cancer, mole changes and serious whole-body reactions; they show association, not proof of cause, and many patients also used sunbeds.

  • Melanoma: for example, a 20-year-old woman had a melanoma removed 3 months after 3–4 weeks of self-injected MT2 and sunbed use.[11]
  • Systemic toxicity: a man who injected 6 mg developed a fast heart rate and severe muscle breakdown (rhabdomyolysis) and needed 3 days of intensive care.[12]
  • Priapism: a refractory ischemic case needed surgical treatment.[13]

For how the FDA views products like this in general, see are peptides safe?

Other peptide pages

The peptides most often looked up alongside this one. Each page gives that peptide's FDA status, compounding status and published human evidence, with sources; the status table has all 23 in one place.

Frequently asked questions

Is melanotan II FDA-approved?

No. It has never been approved, and the FDA has treated it as an unapproved new drug since at least 2007.[1][6]

Is MT2 the same as PT-141?

No. PT-141 is bremelanotide, a related but different molecule approved as Vyleesi for low sexual desire in premenopausal women.[15] MT2 itself is not approved.

Can melanotan cause melanoma?

Case reports describe melanoma and changes in moles after melanotan use, often together with sunbeds. They show an association, not proof of cause, and the FDA cites them among its safety concerns.[11][2]

Is melanotan II banned in sport?

It is not named on the WADA 2026 list, but WADA's S0 class covers substances with no current approval for human use.[17]

Sources

  1. openFDA Drugs@FDA searches for AOD-9604, KPV, epitalon, semax, selank, cagrilintide, melanotan and NAD (no application found) · openFDA, searched November 13, 2026
  2. Certain bulk drug substances for use in compounding that may present significant safety risks · U.S. Food and Drug Administration, content current April 22, 2026
  3. February 2027 meeting of the Pharmacy Compounding Advisory Committee (agenda: cathelicidin LL-37, GHK-Cu, dihexa acetate, melanotan II, pegylated mechano growth factor) · U.S. Food and Drug Administration, content current April 15, 2026
  4. Warning letter: Tailor Made Compounding LLC · U.S. Food and Drug Administration, April 1, 2020
  5. Import Alert 66-41: unapproved new drugs promoted in the U.S. · U.S. Food and Drug Administration, published November 12, 2026
  6. Debarment order: Melanocorp owner, after unapproved melanotan II sales (81 FR 79501) · U.S. Food and Drug Administration, Federal Register, November 14, 2016
  7. MHRA freedom of information response 21/1237: melanotan II · UK Medicines and Healthcare products Regulatory Agency, December 20, 2021
  8. Dorr RT et al. Melanotan-II pilot phase 1 study in healthy men (Life Sci 1996;58:1777–84) · Life Sciences, 1996
  9. Wessells H et al. Melanotan II in men with psychogenic erectile dysfunction (J Urol 1998;160:389–93) · PubMed 9679884, 1998
  10. Wessells H et al. Melanotan II in men with organic erectile dysfunction (Urology 2000;56:641–6) · Urology, 2000
  11. Hjuler KF, Lorentzen HF. Melanoma associated with melanotan-II (Dermatology 2014;228:34–6) · PubMed 24355990, 2014
  12. Nelson ME et al. Melanotan II injection resulting in systemic toxicity and rhabdomyolysis (Clin Toxicol 2012;50:1169–73) · PubMed 23121206, 2012
  13. Mallory CW et al. Refractory ischemic priapism after melanotan II (Sex Med 2021;9:100298) · PubMed 33460908, 2021
  14. NCT07437560: melanotan II with narrowband UVB for vitiligo (phase 2, registered 2026) · ClinicalTrials.gov, accessed November 13, 2026
  15. Vyleesi (bremelanotide) prescribing information · FDA label via openFDA, effective November 5, 2026
  16. Drugs@FDA: Scenesse (afamelanotide) implant, NDA 210797 · openFDA, approved October 8, 2019
  17. World Anti-Doping Code: Prohibited List 2026 · World Anti-Doping Agency, in effect January 1, 2026
  18. PubChem CID 92432: melanotan II · PubChem, NCBI, accessed November 13, 2026