To preliminarily explore the spectrum of effectiveness and tolerability of the new
antiepileptic drug topiramate in bipolar disorder, we evaluated the response of 56
bipolar outpatients in the Stanley Foundation Bipolar Outcome Network (SFBN) who had
been treated with adjunctive topiramate in an open-label, naturalistic fashion.
In this case series, response to topiramate was assessed every 2 weeks for the first
3 months according to standard ratings in the SFBN, and monthly thereafter while patients
remained on topiramate. Patients' weights, body mass indices (BMIs), and side effects
were also assessed.
Of the 54 patients who completed at least 2 weeks of open-label, add-on topiramate
treatment, 30 had manic, mixed, or cycling symptoms, 11 had depressed symptoms, and
13 were relatively euthymic at the time topiramate was begun. Patients who had been
initially treated for manic symptoms displayed significant reductions in standard
ratings scores after 4 weeks, after 10 weeks, and at the last evaluation. Those patients
who were initially depressed or treated while euthymic showed no significant changes.
Patients as a group displayed significant decreases in weight and BMI from topiramate
initiation to week 4, to week 10, and to the last evaluation. The most common adverse
side effects were neurologic and gastrointestinal.
These preliminary open observations of adjunctive topiramate treatment suggest that
it may have antimanic or anticycling effects in some patients with bipolar disorder,
and may be associated with appetite suppression and weight loss that is often viewed
as beneficial by the patient and clinician. Controlled studies of topiramate's acute
and long-term efficacy and side effects in bipolar disorder appear warranted.