Stevens-Johnson syndrome (SJS) is a cutaneous mucosal disorder characterized by extended necrosis and detachment of the epidermis affecting <10% of the body surface, caused by drugs or infections. The authors report a case of a girl with Depakine resistant epilepsy, who develops a SJS in the third week of introducing lamotrigine. The girl also presents an acute diarrheal disease with double viral etiology - rotavirus and norovirus. The clinical image comprises polymorphic erythematous maculopapular exanthema with vesicular and bullous elements, with ulcerations and desquamations at the level of the eyelids, mouth, anogenital area and tegument denuding at the level of the abdomen and limbs. The SCORTEN score (SCORe of Toxic Epidermal Necrosis) for establishing the seriousness is 1. The evolution of the disease is slowly favorable under conservative treatment, which does not involve the use of corticotherapy or intravenous immunoglobulins. Although there is a low incidence of this syndrome in pediatrics, it may occur as complication of using some drugs - mostly anti-epileptics or antibiotics, corroborated or not with an infectious process.