Our report concerns 2 patients who developed delirium after an epileptic attack during mianserin treatment. In both cases the EEG showed a change with periodic sharp slow complexes similar to that seen in Creutzfeldt-Jakob disease. The symptoms subsided, however, and the EEG normalized after the antidepressant was discontinued, suggesting a noxious response to mianserin. If Creutzfeldt-Jakob-like changes in the EEG occur, the possible effect of antidepressant medication should be considered.