Phenytoin a new modality in treatment of vitiligo

Vitiligo is a prevalent acquired depigmenting condition influencing about 0.5 to 2 percent of the worldwide population. It is marked by the selective destruction of epidermal melanocytes through multifactorial mechanisms, with autoimmune dysfunction considered the primary pathogenic pathway. Various treatment options, including calcineurin inhibitors, topical corticosteroids, phototherapy, vitamin D analogues, systemic immunomodulators, antioxidants, and surgical interventions, have shown variable efficacy. Intralesional and topical corticosteroids remain 1st-line therapies owing to their ability to suppress lymphocyte activity, reduce pro-inflammatory cytokines, and limit antigen presentation. However, long-term use is limited by local side effects like skin atrophy. Phenytoin, traditionally used as an anticonvulsant and antiarrhythmic agent, has recently emerged as a potential therapeutic option for vitiligo. Beyond its immunomodulatory properties, phenytoin promotes fibroblast proliferation, collagen deposition, stabilization of melanosome membranes, and melanocyte proliferation. Importantly, it inhibits cytotoxic T-lymphocyte activation and shifts the immune response toward a Th2 profile. Clinical and experimental evidence also suggests that phenytoin may prevent corticosteroid-induced skin atrophy when used concomitantly, thereby enhancing treatment outcomes. Given these immunosuppressive and melanogenic effects, phenytoin represents a promising novel approach in vitiligo management. This research has been therefore designed to assess the clinical efficiency and safety of topical and intralesional phenytoin compared to topical and intralesional corticosteroids in treating stable non-segmental vitiligo vulgaris. By assessing both therapeutic response and potential side effects, this work aims to provide further insight into the role of phenytoin as an alternative or adjunctive modality to standard corticosteroid-based therapies.