[1] BD-NOS was a classification in the DSM-IV and has since been changed to Bipolar "Other Specified" and "Unspecified" in the 2013 released DSM-5 (American Psychiatric Association, 2013).
BD-NOS is a disorder which creates intense mood instability which causes bouts of depression, hypomania, and mania, and occasionally mood stability.
The diagnosis of bipolar NOS is indicated when there is a rapid change (days) between manic and depressive symptoms and can also include recurring episodes of hypomania.
Bipolar NOS may be diagnosed when it is difficult to tell whether bipolar is the primary disorder due to another general medical condition, such as a substance use disorder.
[3][4] Individual approaches to treatment are recommended, usually involving a combination of mood stabilizers and atypical antipsychotics.