Melanotan II (MT-II) is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone (α-MSH). It interacts with multiple melanocortin receptor subtypes, including MC1R, MC3R, MC4R, and MC5R, making it a research compound of interest in melanocortin pharmacology and pigmentation-related signaling.

Laboratory and clinical research has investigated Melanotan II in relation to melanogenesis, melanocortin receptor signaling, appetite-related pathways, and neuroendocrine activity. However, Melanotan II is not FDA-approved for any therapeutic indication, and its safety profile has not been established for consumer use.

Research involving Melanotan II should be conducted under appropriate laboratory controls and applicable regulatory requirements. It should not be presented as an approved tanning, cosmetic, sexual-function, or therapeutic product.