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Category 2 — Restricted

Melanotan II — MT-II

Skin Pigmentation. Melanotan II is a synthetic analog of α-melanocyte-stimulating hormone (α-MSH) that stimulates melanogenesis — the produ...

Sequence
Cyclic Heptapeptide
Category
Category 2
Primary Use
Skin Pigmentation
Administration
SubQ

What Is Melanotan II?

Melanotan II is a synthetic analog of α-melanocyte-stimulating hormone (α-MSH) that stimulates melanogenesis — the production of melanin, the pigment responsible for skin and hair color. Originally developed at the University of Arizona as a potential sunless tanning agent, it remains one of the most widely known (and controversial) peptides.

pigmentation tanning melanocortin α-MSH restricted

Mechanism of Action

Melanotan II activates melanocortin receptors (MC1R through MC5R) broadly, which triggers melanin production in melanocytes. Its non-selective receptor binding is responsible for both its tanning effects (MC1R) and its side effect profile — including sexual arousal (MC4R), appetite suppression (MC4R), and potential cardiovascular effects (MC3R/MC4R).

Key Research Findings

  • Melanogenesis — Clinical studies confirm dose-dependent increases in skin pigmentation after UV exposure
  • Sexual function — Documented pro-sexual effects led to development of PT-141 (which isolates this mechanism)
  • Appetite suppression — MC4R activation produces notable appetite reduction
  • Photoprotection — Increased melanin may provide some UV protection, though this does not replace sunscreen
  • Safety concerns — Case reports link MT-II to nevi (mole) changes, which raises melanoma surveillance concerns

Important: The evidence base for Melanotan II varies by application. Many findings are from preclinical (animal or in vitro) studies. Large-scale human clinical trials may not be completed. Always evaluate the quality of evidence before drawing conclusions.

Known Side Effects

Significant side effect profile: nausea (very common, especially at higher doses), facial flushing, fatigue, and injection site reactions. More concerning: cardiovascular effects, changes in existing moles (nevi), potential melanoma risk with long-term use, and priapism. These safety concerns are why it remains Category 2.

Legal Status (2026)

Melanotan II remains on the FDA's Category 2 (restricted) list due to cardiovascular effects, melanoma concerns, and significant adverse event profiles. It cannot be legally compounded. Available as a research chemical only.

Where to Buy Melanotan II for Research

These verified suppliers carry Melanotan II with third-party COAs and US-based shipping.

BP
BioPure Peptides
USA-made · 99%+ purity · WHO/GMP certified
  • Third-party tested with COAs on every batch
  • Ships from Chandler, AZ — free shipping over $200
  • 30+ peptides in catalog including blends and stacks
Shop BioPure Peptides →
MW
Midwest Peptide
Mission, KS · Same-day shipping · COAs on every page
  • Same-day UPS shipping from US facility
  • Free shipping on every order
  • 5% additional discount with Zelle payment
Use code POWER for 10% off
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