Acute psychosis and EEG normalisation after vagus nerve stimulation

The acute appearance of psychosis on achievement of seizure control and normalisation of a previously abnormal EEG has long been recognised as a clinical entity termed “forced normalisation”.1 Focal and generalised epilepsies are both implicated.1 Most of the old and new antiepileptic drugs have been implicated in the emergence of psychosis with EEG normalisation.1 2 Chronic vagus nerve stimulation has been proposed as an effective and safe treatment of medically intractable epilepsy, although the mechanism of action and the specific indications of this treatment remain unknown. Side effects are limited and no serious or life threatening damage has been reported.3 The case of a patient with medically intractable epilepsy who developed a schizophrenia-like psychosis when control of seizures and scalp EEG normalisation were achieved through vagus nerve stimulation is presented. A 35 year old man had had intractable left frontotemporal epileptic seizures since the age of 10 years. He is right handed and left language dominant. Up to the age of 25 years he was almost free of seizures under treatment with carbamazepine and phenobarbital. After that …