Interferon-treated patients can present seizures, which in most paediatric cases are related to fever. The case of chronic hepatitis C is described in which Interferon probably disclosed a latent epilepsy. The hypothesis is advanced that seizures can be provoked by Interferon therapy in subjects with a low convulsant threshold and, in those cases in which it cannot be substituted with another drug, antiepileptic therapy should be started after the first episode.