Olanzapine-induced electroencephalographic changes reversed by lamotrigine

The atypical neuroleptic, olanzapine (OLZ), may induce electroencephalographic (EEG) abnormalities. The anticonvulsant, lamotrigine (LMG), reduces interictal epileptiform discharges and is effective in seizures in patients with both primary and partial epilepsy syndromes. The effect of LMG on neuroleptic-induced EEG abnormalities has not been previously reported. We describe the case of a 13-year-old male with paroxysmal nonepileptic spells who underwent diagnostic video-EEG telemetry, whose abnormal OLZ-induced EEG findings were strikingly affected by LTG withdrawal and reintroduction. The effect of LTG in normalizing EEG changes in suspected epilepsy caused by atypical neuroleptics is discussed.