LITHIUM AUGMENTATION OF VALPROIC ACID IN TREATMENT-RESISTANT DEPRESSION

An open trial was conducted to assess the efficacy of valproic acid monotherapy and in combination with lithium in a highly refractory sample of 10 patients. Two of the patients had major depression (unipolar) and had failed to respond to two adequate trials of antidepressants. Eight patients had bipolar depression and had failed to respond to lithium and/or carbamazepine trials, and also had a history of antidepressant induced mania. Efficacy was assessed using the Clinical Global Impression Scale, the Hamilton Psychiatric Rating Scale for Depression, and the Montgomery-Asberg Depression Rating Scale. Subjects first received valproic acid for an average of 4 weeks, followed by lithium addition. The two unipolar subjects responded to valproic acid alone. Significant treatment effects were obtained for all three measures 1 week after lithium addition. These findings suggest that valproic acid alone or in combination with lithium is effective in treating refractory depression.