Beyond Sleeping Disorders, the Role of Melatonin in Skin Diseases and Emerging Applications in Dermatology and Topical Therapy

Melatonin, traditionally recognized for its role in regulating circadian rhythms and sleep, has emerged as a multifunctional molecule with significant implications in dermatology. Melatonin is described here as a pleiotropic, context-dependent modulator with antioxidant-related and immunomodulatory actions that are supported by both direct chemical scavenging in cell-free systems and indirect, enzyme-mediated effects in cells and tissues; its antitumor activity in dermatology is primarily preclinical and remains to be confirmed in large clinical trials. Melatonin protects skin cells from oxidative stress, UV radiation, and environmental damage by directly scavenging free radicals and activating endogenous defense systems. It also modulates immune responses, making it relevant in inflammatory dermatoses such as atopic dermatitis, while promoting tissue repair in wound healing and reducing signs of skin aging. Particular attention is given to topical formulations, including gels, creams, and patches, which enable localized delivery, improved skin penetration, and reduced systemic side effects. The review also discusses ongoing clinical trials, delivery technologies, and the potential for combinatorial therapies with established dermatological agents.