Often individuals have also had one or more Major Depressive Episodes. Episodes of Substance-Induced Mood Disorder (due to the direct effects of a medication, other somatic treatments for depression, a drug of abuse, or toxin exposure) or of Mood Disorder Due to a General Medical condition do not count toward a diagnosis of Bipolar I Disorder. In addition, the episodes are not better accounted for by Schizoaffective Disorder and are not superimposed on Schizophrenia, Schizophreniform Disorder, Delusional Disorder, or Psychotic Disorder Not Otherwise Specified. Bipolar I Disorder is sub classified in the fourth digit of the code according to whether the individual is experiencing a first episode (i.e., Single Manic Episode) or whether the disorder is recurrent. Recurrence is indicated by either a shift in the polarity of the episode or an interval between episodes of at least two months without manic symptoms. A shift in polarity id defines as a clinical course in which a Major Depressive Episode evolves into a Manic Episode or a Mixed Episode evolves into a Major Depressive Episode.
