Evaluation of the effect and mechanism of action of local phenytoin in treatment of vitiligo.

There are many theories explaining vitiligo such as genetic, autoimmune, neural, free radicals, biochemical, intrinsic defect, melanocytorrhagy, and convergent theories. Phenytoin is a widely used anticonvulsant, which is used in cutaneous medicine for treatment of ulcers and epidermolysis bullosa. The aim of this study is to assess the effectiveness of topical phenytoin gel in the treatment of vitiligo patients and explaining the underlying mechanism using immunohistochemistry for evaluation of HMB45, CD4, and CD8.