What defines bipolar 2 disorder?

Bipolar II disorder is characterized by the presence of at least one hypomanic episode and one major depressive episode, while not including any full manic episodes. Hypomania is a less severe form of mania, with symptoms that do not lead to severe functional impairment or require hospitalization. The depressive episodes in bipolar II can significantly impair daily functioning and quality of life.

This distinction is crucial because it differentiates bipolar II from other mood disorders, particularly bipolar I disorder, where at least one full manic episode is present. Thus, the requirement of having hypomanic and depressive episodes, but not manic episodes, accurately defines bipolar II disorder. Understanding these criteria is essential for effective diagnosis and treatment planning in clinical practice.