“…1 Despite the infections (especially HSV) being considered as the main cause of EEM, as opposed to SJS and TEN, whose etiology is largely due to drugs, their association with drug reactions is described in the literature (in particular: sulfonamides, phenytoin, NSAIDs and allopurinol). 1,4,3,5 Allergic reactions to drugs are traditionally classified according to Coombs and Gell as the following: immediate hypersensitivity reactions (Type I), cytotoxic reactions (Type II), immune-mediated (Type III) reactions and delayed hypersensitivity reactions (Type IV-mediated by T cells). 6.7 According to the latest knowledge about the function of T cells, Type IV reactions were subclassified as IVa-IVd, with the reactions associated with type IVc: maculopapular, bullous and neutrophilic skin reactions (with a prevalence of SJS and TEN), in which the role of cytotoxic T cells predominates through cytotoxicity mediated by CD8+ T cells, with the destruction of keratinocytes.…”