Adjunctive quetiapine in bipolar patients partially responsive to lithium or valproate

Despite therapeutic treatment with lithium or valproate, patients with bipolar I disorder often require adjunctive therapy to treat persistent symptoms. In order to evaluate the effects of quetiapine for bipolar symptoms inadequately responsive to mood stabilizers, a retrospective chart review was undertaken at the Veterans Affairs (VA) Long Beach Mood Disorders Clinic for all bipolar I outpatients who had been prescribed adjunctive quetiapine during an 18-month study period. Among 75 lithium- or valproate-treated patients receiving quetiapine, 16 were identified in whom therapeutic treatment with lithium (> or =0.8 meq/l) or valproate (> or =75 microg/ml) could be verified during the 2-month period prior to quetiapine initiation. Chart notes were utilized by the principal investigator to assign Clinical Global Impression Bipolar ratings (CGI-BP) before and after 30-120 days of quetiapine treatment (mean=173+/-157 mg). Nine of 16 lithium- or valproate-stabilized bipolar patients (56%) were judged much or very much improved in CGI-BP overall ratings following adjunctive quetiapine. In addition, for the entire sample, quetiapine augmentation resulted in significant improvements in clinician-rated bipolar severity scores (CGI-BP) for mania, depression, and overall bipolar illness. The majority of quetiapine-related symptomatic improvement was due to diminished insomnia, agitation, irritability, and mood disturbance. Side effects were mild and transitory including sedation and dizziness. Low-dose quetiapine may be a useful and well-tolerated adjunct for some bipolar patients with incomplete response to lithium or valproate.