Definition of Bipolar Disorder I

Manic Episode Length

For a bipolar I diagnosis, a manic episode must typically last at least seven days and not be caused by alcohol or drugs, according to the National Institute of Mental Health (NIMH.)

Depressive Episode Length

Depressive episodes in Type I bipolar disorder must last at least two weeks to merit that diagnosis, according to the NIMH.

Exceptions

In some cases, a patient's mania may last less than seven days but be so severe that bipolar I is the best diagnosis, the NIMH reports.

Psychotic Symptoms

Psychotic symptoms such as hearing voices or seeing things, along with mania and depression, usually indicate bipolar I, according to the NIMH, as opposed to other types of manic depression.

Severity

The depressive and/or manic episodes associated with bipolar disorder are a major change from the patient's normal behavior and affect function at home work, or school, according to the NIMH. Bipolar disorder is a mental illness characterized by alternating moods of depression and mania. Mania is a state of over-elation in which one can engage in impulsive and risky behaviors, such as overspending. Bipolar I is one of several possible manic-depressive-related diagnoses.