To examine the efficacy of lithium and valproate in Bipolar I patients suffering from a manic episode with previous EEG abnormalities.

Fifteen patients of both sexes were included in four weeks, prospective, observational, open-label treatment trial. They met criteria: Bipolar I affective disorder (manic episode) according to ICD-10 and EEG abnormalities (high voltage, 10-13 cps alpha, “iritative”, sharp activity). Patients were divided into two groups: Group I – seven patients (4 male and 3 female) treated with lithium 900 mg/day, haloperidol 10 mg/day and chlorpromazine 150 mg/day and Group II – eight patients (4 male and 4 female) treated with valproate 1000 mg/day, haloperidol 10 ma/day and 150 mg/day. Severity of illness and treatment efficacy were measured with Young Mania Rating Scale (YMRS) at the start point, after 2 and 4 weeks, along with conventional EEG registration.

Throughout observational period, lithium treated patients (Group I) did not expressed any improvement in EEG (continuously showing high voltage, sharp alpha activity). Meanwhile, Group II (valproate) patients, after 2 weeks of treatment expressed clear EEG stabilisation. In addition, after 4 week of lithium appliance (Group I) there is no significant reduction in YMRS-score. Group II (valproate) patients after 2 weeks achieved significant clinical improvement (significance level p<0,05) and after 4 weeks highly significant YMRS-score reduction (p<0,01).

Conventional EEG may be useful in therapeutic prediction in a manner that patients with EEG abnormalities had better respond to anticonvulsant mood stabilizers than lithium.