Sodium valproate "encephalopathy": report of three cases with generalised epilepsy.

A report of 3 cases of sodium valproate "encephalopathy". The addition of valproate to the treatment in 3 subjects, two adults and one child, all with generalised epilepsy, induced a worsening of the clinical and EEG pattern and in one case disturbances of vigilance as well. The occurrence of this complication in generalised epilepsy and the possibility that EEG alterations are its only manifestation are emphasised.