Bipolar II disorder

Bipolar II disorder (BP-II; pronounced "type two bipolar disorder") is a bipolar spectrum disorder (see also Bipolar disorder) characterized by at least one episode of hypomania and at least one episode of major depression. Diagnosis for bipolar II disorder requires that the individual must never have experienced a full manic episode (unless it was caused by an antidepressant medication; otherwise one manic episode meets the criteria for bipolar I disorder). Hypomania is a sustained state of elevated or irritable mood that is less severe than mania and does not significantly impact quality of life. Unlike mania, hypomania is not associated with psychosis. The hypomanic episodes associated with bipolar II disorder must last for at least four days. Commonly, depressive episodes are more frequent and more intense than hypomanic episodes. Additionally, when compared to bipolar I disorder, type II presents more frequent depressive episodes and shorter intervals of well-being. The course of bipolar II disorder is more chronic and consists of more frequent cycling than the course of bipolar I disorder. Finally, bipolar II is associated with a greater risk of suicidal thoughts and behaviors than bipolar I or unipolar depression. Although bipolar II is commonly perceived to be a milder form of Type I, this is not the case. Types I and II present equally severe burdens.