Bipolar disorder

Disorder of depression and mood episodes

Bipolar disorder (BD), previously known as manic depression, is a mental disorder characterized by periods of depression and abnormally elevated mood, lasting days to weeks, and in some cases months. If the elevated mood is severe or associated with psychosis, it is called mania; if it does not significantly affect functioning, it is called hypomania. During mania, an individual behaves or feels abnormally energetic, happy, or irritable, and often makes impulsive and reckless decisions.

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