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Article Abstract

Bipolar II disorder is frequently misdiagnosed as major depressive disorder. In particular, correctdiagnosis of bipolar II disorder may be delayed by years due to the predominance of depressive symptomsand the relative subtlety of hypomania, which may manifest only briefly and without elevatedmood. The prevalence of bipolar II disorder varies from 0.5% to about 5% depending on the criteriaused. Diagnosis can be improved by using mood disorder questionnaires, systematic probing, and prospectivemood diary charting. There is a dearth of research into treatment of bipolar disorder. The limitedavailable evidence suggests that lithium and lamotrigine may have efficacy in preventing relapseof mood episodes. Acute bipolar II depression could be treated with a combination of a mood stabilizerplus an antidepressant or pramipexole and in rare cases with antidepressant monotherapy. Hypomaniawill likely respond to monotherapy with antimanic agents. Adjunctive psychosocial treatmentsmay provide additional benefit in patients with bipolar II disorder.