Objective: To assess the effectiveness and safety of oxcarbazepine (OXC) in bipolar disorder (BD) and related conditions.
Methods: We reviewed medical records of patients given OXC treatment between March 2003 and March 2005 at the University of British Columbia Hospital. Response to treatment was assessed retrospectively using the Clinical Global Impression of Severity (CGI-S), and the Clinical Global Impression of Improvement (CGI-I) scales.
Results: OXC was prescribed to 15 patients with bipolar I (n = 12), bipolar II (n = 2) and schizoaffective (n = 1) disorder who presented with depression (n = 9), mania (n = 3), hypomania (n = 1), or mixed state (n = 2). Six patients had Axis II diagnoses and 10 patients had a family history of mood disorders. Psychiatric co-morbidity was found in four patients. The mean daily dose of OXC was 775 ± 556.11 mg/day and the mean duration of follow-up was 31.60 ± 41.51 weeks. The OXC add-on led to a significant reduction in symptoms as indicated by reduction in CGI-S scores at 1 and 2 months. Nine of 12 patients at 1 month and seven of 14 at 1 or 2 months were much or very much improved on CGI-I scale. One patient (7%) developed hyponatremia. Six patients (40%) experienced no side effects and three patients (20%) stopped the medication because of side effects.
Conclusion: OXC was effective and well-tolerated in refractory BD and schizoaffective disorder. These preliminary data are promising but controlled studies are needed to confirm its efficacy in refractory BD.