Bipolar disorder is a chronic, recurring illness that requires long-term prophylactic treatment. However, treatment is often complicated by misdiagnosis and inappropriate medication selection. A number of therapies are available for the treatment of bipolar disorder and the ultimate therapeutic choice depends on the individual patient's current symptoms, disease history, and comorbid illnesses. However, research is needed to improve the overall prognosis for patients with bipolar depression, particularly because approximately 20% of patients commit suicide. Mania is the most dramatic expression of bipolar disorder and may overshadow the impact of the depressive phase of the illness. Compared with mania, episodes of bipolar depression are more frequent, of longer duration, and are associated with higher rates of morbidity and mortality. Therefore, successful treatment and prevention of bipolar depression remains an essential treatment goal.