Atypical Antipsychotics in Bipolar Depression: Neurobiological Mechanisms and Application to Treatment

Seo, Ho Jun; Woo, Young Sup; Bahk, Won Myong

Abstract

Bipolar depression is a difficult-to-treat and disabling form of depression. Because of the dramatic and impressive nature of mania, depression is often the overlooked facet of bipolar disorder. However, it is becoming apparent that depressive episodes in bipolar disorder are more numerous, longer lasting, and more difficult to treat than mania, and are a significant burden on the life of the average person with bipolar disorder. These burdens may include more days spent ill, greater impairment of vocational and cognitive functioning, reduced quality of life, and increased risk of suicide. Though researchers have recently recognized the clinical importance of bipolar depression, up-to-date treatment options for bipolar depression are insufficient, and their application in clinical practice is limited in many ways. Surprisingly few controlled studies have been conducted on the treatment of bipolar depression. The recent introduction of atypical antipsychotics, with their more favorable safety profile, has resulted in significant changes in the management of bipolar disorder and has proven beneficial across the spectrum of moods found in bipolar disorders. Many clinicians have been particularly interested in recent findings of atypical antipsychotics, which are especially effective in treating bipolar depression. This article will briefly review studies related to the neurobiology of bipolar depression and will discuss the implications of using atypical antipsychotics to treat bipolar depression, focusing on dopaminergic and serotonergic systems.