SummaryTopiramate is an antiepileptic agent, which is being investigated as a mood-stabilizer. Three obese individuals with DSM-IV bipolar I disorder and type II diabetes mellitus received topiramate treatment in combination with antipsychotics and valproate or carbamazepine. In addition to improved mood stability, these individuals lost between 16 to 20.5% of their pre-topiramate body weight and also achieved significant glycemic control.