Bipolar depression: pharmacotherapy and related therapeutic strategies

The depressed phase of bipolar affective disorder is a significant cause of suffering, disability, and mortality and represents a major challenge to treating clinicians. This article first briefly reviews the phenomenology and clinical correlates of bipolar depression and then focuses on the major pharmacological treatment options. We strongly recommend use of mood stabilizers as the first-line treatment for the type I form of bipolar depression, largely because longer-term preventative therapy with these agents almost certainly will be indicated. Depressive episodes that do not respond to lithium, divalproex, or another mood stabilizer, or episodes that "breakthrough" despite preventive treatment, often warrant treatment with an antidepressant or electroconvulsive therapy. The necessity of mood stabilizers in the type II form of bipolar depression is less certain, aside from the rapid cycling presentation. Both experts and practicing clinicians recommend bupropion and the selective serotonin reuptake inhibitors as coequal initial choices, with venlafaxine and monoamine oxidase inhibitors, such as tranylcypromine, preferred for more resistant cases. The risk of antidepressant-induced hypomania or mania with concomitant mood stabilizer therapy is low, on the order of 5% to 10% during acute phase therapy. Additional therapeutic options and optimal durations of therapy also are discussed.