Antipsychotic treatment is frequently associated with unspecific EEG abnormalities; however, in a minority of subjects under antipsychotics severe alterations of brain electric activity including epileptiform activity might occur. Consequently, the risk of seizures is increased under psychopharmacology; however, differences between classes of antipsychotics (e.g. first or second generation drugs) have not been studied extensively and risk profiles regarding changes in brain electric activity remain to be established yet. We investigated psychiatric patients under antipsychotic medication using routine clinical neurophysiological assessments and compared first and second generation drugs. Aim of the study was to estimate the risk of EEG abnormalities under either class of medication by using both visual (standard) and quantified electroencephalography (qEEG) and to analyse the clinical relevance of such findings. In addition the association of brain electric activity under antipsychotics as assessed by novel electromagnetic imaging techniques with clinical parameters such as symptomatology or drug response was investigated.

There were significant differences in the prevalence of EEG abnormalities between first and second generation antipsychotics, with severe abnormalities being more pronounced under some of the second generation drugs. The use of either class was safe in general, but the differences might be of relevance in subjects with a history of seizures. The use of qEEG techniques in the clinical setting in terms of characterising the patients and the respective responses to medication will further be discussed.