Topiramate treatment of bipolar spectrum disorders: a retrospective chart review.

The objective of this paper was to determine if topiramate is effective as treatment for bipolar spectrum disorders in a naturalistic setting. All charts of outpatients treated with topiramate (n = 76) were reviewed, and clinical response was assessed retrospectively using the Clinical Global Impressions Scale for Improvement. Mild improvement was seen in 47% (n = 36) and moderate-to-marked improvement in 13% (n = 10). Responders received a higher mean dose (180 mg/day) than did nonresponders (83.2 mg/day, p = 0.002). Topiramate dose was also higher in those who lost weight (138.3 mg/day) than in those who did not (70 mg/day, p = 0.007). Weight loss was experienced by 50% of the sample, with a mean loss of 14.2 lbs. Side effects were reported by 82% (n = 62) of the population, including cognitive effects, sedation, parasthesias, nausea, insomnia, headache, and dizziness. Adverse effects led 36% (n = 27) of the total sample to discontinue treatment with topiramate. Topiramate led to significant weight loss in about half of this bipolar population, while also improving mood symptoms at least mildly in most patients. Topiramate response and weight loss were both dose-related, with efficacy, in particular, associated with higher doses (mean = 180 mg/day) than frequently used in current clinical practice.