A preliminary open-label study of zonisamide treatment for bipolar depression in 10 patients.

Objective: The purpose of this study was to investigate the effectiveness of zonisamide in the treatment of bipolar depression.

Method: Ten patients with DSM-IV bipolar disorder, depressed phase, who had either not tolerated or not responded to previous treatments were given zonisamide in this add-on open-label study. Zonisamide treatment was started at 100 mg/day and increased by 100 mg every 2 weeks to a maximum of 300 mg/day in divided doses (b.