The concept of alternate psychosis was developed from observations in 1953 by Landoldt, of an inverse relationship between seizure control and psychotic symptom occurrence, in which he observed a 'normalization' of EEG recordings with the appearance of psychiatric symptoms and coined the term 'forced normalization' . This antagonism between psychosis and epilepsy has been considered by some as the explanation for the therapeutic effect of ECT of psychotic disorders. Forced normalization has been reported in patients with temporal lobe epilepsy and generalized epilepsies; this phenomenon is relatively rare.
Forced normalization presents as a pleomorphic clinical disorder with a paranoid psychosis without clouding of consciousness being the most frequent manifestation. As with other POEs, a richness of affective symptoms has been identified.
The phenomenon of forced normalization has been observed following the use of various AEDs, including phenyl-acetylurea, phenytoin and primidone, valproate and carbamazepine and, more recently, vigabatrin and levetiracetam. In these cases, however, the psychotic disorder was thought to result from the suppression of seizures rather than reflecting an adverse event of the AED. An iatrogenic effect of the AED has to be considered in the differential diagnosis of these patients, however.
Was this article helpful?