Bipolar disorder, previously known as manic depression, is a mental disorder characterized by periods of depression and abnormally elevated moods.If the elevated mood is severe or associated with psychosis, it is called mania; if it is less severe, it is called hypomania. During mania, an individual behaves or feels abnormally energetic, happy, or irritable.Individuals often make impulsive decisions with little regard for the consequences.There is usually a reduced need for sleep during manic phases.During periods of depression, individuals may experience crying, a negative outlook on life, and poor eye contact with others.The risk of suicide is high; over a period of 20 years 6% of people died by suicide, while 30-40% engaged in self-harm.Other mental health issues, such as anxiety disorders and substance use disorders, are commonly associated with bipolar disorder.