What Is Melanotan I (Melanotan-1 / Afamelanotide)?

Melanotan I (melanotan-1) is a synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH), a peptide studied in the laboratory for its activity at melanocortin receptors involved in pigmentation. The closely related synthetic α-MSH analog afamelanotide is an approved medicine for a rare light-sensitivity disorder called erythropoietic protoporphyria (EPP). The Melanotan I sold here is supplied strictly as a research material for research use only (RUO) — it is not a drug, not the approved medicine, and is not for human use.

Quick facts

• Class: synthetic α-MSH analog / melanocortin-receptor agonist
• Research focus: melanocortin-receptor signaling and pigmentation research
• Primary target studied: the melanocortin-1 receptor (MC1R)
• Regulatory status: research materials are RUO; the related analog afamelanotide has an approved medical use for EPP
• Not for human use: for in-vitro and laboratory research only

What is Melanotan I?

Melanotan I refers to a synthetic peptide modeled on α-MSH, one of the body’s natural melanocortin hormones. In the research literature, the most-studied compound in this family is afamelanotide — chemically [Nle4, D-Phe7]-α-MSH (also written NDP-α-MSH) — which differs from natural α-MSH at two amino-acid positions, changes that make the molecule more stable and longer-acting in laboratory studies. Because melanocortin peptides act on receptors that influence melanin production, Melanotan I has been used in preclinical and clinical research as a tool to probe pigmentation biology. Any references to effects below describe findings in controlled research settings, not outcomes for a consumer.

Melanotan I vs Melanotan II

These are two distinct peptides that are easy to confuse. The key difference is selectivity. Melanotan I is a more selective α-MSH analog whose research has centered on the melanocortin-1 receptor (MC1R). Melanotan II is a different, structurally smaller and broader melanocortin agonist that interacts with a wider set of melanocortin receptors (including MC3R and MC4R) in laboratory studies. Same hormone family, different molecules, different receptor profiles. For more, see our Melanotan II article and our full Melanotan I vs Melanotan II comparison.

Mechanisms studied in the lab

• MC1R agonism: Melanotan I peptides bind and activate the melanocortin-1 receptor (MC1R) on pigment-producing cells in research models.
• Eumelanin synthesis: MC1R activation has been studied for its role in driving production of eumelanin, the darker melanin pigment.
• MC1R variants: research has examined how α-MSH analogs behave in cells and individuals carrying MC1R variant alleles, which alter receptor signaling.

Research status

It is important to separate the approved medicine from research materials. The synthetic α-MSH analog afamelanotide (brand name Scenesse) was approved by the U.S. FDA in 2019, as a controlled-release subcutaneous implant, to increase pain-free light exposure in adults with erythropoietic protoporphyria (EPP) — a rare inherited photodermatosis. That approval rests on randomized clinical-trial evidence. By contrast, the Melanotan I research material offered here is not that approved product, is not a drug, and is sold strictly for research use only. It has not been evaluated by the FDA for safety or effectiveness in any consumer application and is not intended to diagnose, treat, cure, or prevent any condition.

Handling

Research peptides are typically supplied as a lyophilized (freeze-dried) powder that must be reconstituted before use in the laboratory. For general handling and preparation practices, see our reconstitution guide.

FAQ

Is Melanotan I the same as afamelanotide? They are closely related α-MSH analogs and the names are often used interchangeably in the literature. However, the approved medicine afamelanotide (Scenesse) is a specific, regulated pharmaceutical product. Research materials labeled “Melanotan I” are RUO and are not the approved drug.

How is Melanotan I different from Melanotan II? Melanotan I is a more selective α-MSH analog studied mainly at MC1R, whereas Melanotan II is a separate, broader melanocortin agonist. See our full comparison for details.

Can I use Melanotan I for tanning or any personal use? No. This product is supplied for research use only and is not for human use. We make no human, cosmetic, or therapeutic claims of any kind.

References

1. Fitzgerald LM, et al. Effect of MELANOTAN [Nle4, D-Phe7]-alpha-MSH on melanin synthesis in humans with MC1R variant alleles. Peptides. 2006.
2. Langendonk JG, et al. Afamelanotide for Erythropoietic Protoporphyria. N Engl J Med. 2015.
3. Böhm M, et al. Benefits and risks of chronic melanocortin-1 receptor activation (review). J Eur Acad Dermatol Venereol. 2025.

For research use only. Not a drug, food, cosmetic, or supplement; not for human or veterinary use. Statements have not been evaluated by the FDA.

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