Melanotan I (Afamelanotide) is a synthetic linear analog of α-melanocyte-stimulating hormone (α-MSH) specifically designed for selective melanocortin-1 receptor (MC1R) activation. This research peptide represents a breakthrough in photoprotection research, demonstrating potent and prolonged stimulation of melanogenesis without the broader melanocortin receptor activity of its counterpart Melanotan II. With its enhanced metabolic stability and receptor selectivity, Melanotan I serves as an essential tool for studying skin pigmentation mechanisms, UV protection, and MC1R-specific signaling pathways.