pressive disorder or substance/medication-i nduced bipolar and related disorder (repre-
senting the physiological effects of a medicati on, other somatic treatments for depression,
drugs of abuse, or toxin exposure) or of de pressive and related disorder due to another
medical condition or bipolar and related disord er due to another medi cal condition do not
count toward a diagnosis of bi polar II disorder unless they persist beyond the physiolog-
ical effects of the treatment or substance and then meet duration criteria for an episode. In
addition, the episodes must not be better acco unted for by schizoaffective disorder and are
not superimposed on schizophrenia, schizophreniform disorder, delusional disorder, or
other specified or unspecified schizophrenia spectrum or other psychotic disorders (Cri-
terion C under “Bipolar II Disorder”). The de pressive episodes or hypomanic fluctuations
must cause clinically significant distress or impairment in social, occupational, or other
important areas of functioning (Criterion D under “Bipolar II Disorder ”); however, for hy-
pomanic episodes, this requirement does not have to be met. A hypomanic episode that
causes significant impairment would likely qu alify for the diagnosis of manic episode and,
therefore, for a lifetime diagnosis of bipolar I disorder. The recurrent major depressive ep-
isodes are often more frequent and lengthier than those occurring in bipolar I disorder.
Individuals with bipolar II d isorder typically present to a clinician during a major de-
pressive episode and are unlikely to complain  initially of hypomania. Typically, the hy-
pomanic episodes themselves do not cause im pairment. Instead, th e impairment results
from the major depressive episodes or from a persistent pattern of unpredictable mood
changes and fluctuating, unreliable interperso nal or occupational functioning. Individu-