Acute psychosis during the postictal period in a patient with idiopathic generalized epilepsy: postictal psychosis or aggravation of schizophrenia? A case report and review of the literature.

Postictal psychoses are common comorbid conditions of temporal lobe epilepsy and are reported to be characterized by affective changes. However, postictal psychoses are rare among patients with idiopathic generalized epilepsy, and the causal relationship between postictal psychoses and idiopathic generalized epilepsy is unknown. Here, we report the case of a man who had idiopathic generalized epilepsy and experienced 4 episodes of schizophrenia-like interictal psychosis before the age of 41 years. At the age of 56 years, he experienced a generalized tonic-clonic seizure for the first time in 15 years and developed psychotic symptoms on the next day. Notably, in addition to the schizophrenia-like symptoms, the patient experienced mania-like symptoms such as elated mood, grandiose delusions, agitation, and pressured speech during the last psychotic episode in the postictal period. It was suspected that postictal neuronal processes and a predisposition to endogenous psychosis both contributed to the psychopathology of this episode.