14 patients (age 42.1 +/- 15.5; 12 women, 2 men) with a depressive episode (moderate, mild; ICD-10) were treated with fluvoxamine (150 mg). After 4 weeks two groups with different responses to the drug emerged (10 responders: improvement in Beck Inventory of Depression 13.6 +/- 2.9 and 4 nonresponders: 2.0 +/- 2.4). FFT analysis of their EEG (taken before and after the treatment) showed some relative power differences in most bands of frequencies between groups, mostly marked for à (7-14 Hz) and smaller for the others. Alpha activity was relatively low after treatment in nonresponders and slightly higher in responders. However, none of these results had statistical value.