Bipolar Disorder

Bipolar disorder or bipolar affective disorder (historically known as manic-depressive disorder) is a psychiatric diagnosis for a mood disorder in which people experience disruptive mood swings. These encompass a frenzied state known as mania (or hypomania) usually alternated with symptoms of depression. Bipolar disorder is defined by the presence of one or more episodes of abnormally elevated energy levels, cognition, and mood with or without one or more depressive episodes.

At the lower levels of mania, such as hypomania, individuals may appear energetic and excitable. At a higher level, individuals may behave erratically and impulsively, often making poor decisions due to unrealistic ideas about the future, and may have great difficulty with sleep. At the highest level, individuals can show psychotic behavior, including violence. Individuals who experience manic episodes also commonly experience depressive episodes, or symptoms, or a mixed state in which features of both mania and depression are present at the same time. These events are usually separated by periods of "normal" mood; but, in some individuals, depression and mania may rapidly alternate, which is known as rapid cycling. Severe manic episodes can sometimes lead to such psychotic symptoms as delusions and hallucinations.

The lifetime prevalence of all types of bipolar disorder is thought to be about 4% (meaning that about 4% of people experience some of the characteristic symptoms at some point in their life). Prevalence is similar in men and women and, broadly, across different cultures and ethnic groups. Genetic factors contribute substantially to the likelihood of developing bipolar disorder, and environmental factors are also implicated. Bipolar disorder is often treated with mood stabilizing medications and psychotherapy. In serious cases, in which there is a risk of harm to oneself or others, involuntary commitment may be used. These cases generally involve severe manic episodes with dangerous behavior or depressive episodes with suicidal ideation. There are widespread problems with social stigma, stereotypes, and prejudice against individuals with a diagnosis of bipolar disorder. People with bipolar disorder exhibiting psychotic symptoms can sometimes be misdiagnosed as having schizophrenia.

The current term bipolar disorder is of fairly recent origin and refers to the cycling between high and low episodes (poles). The term "manic-depressive illness" or psychosis was coined by German psychiatrist Emil Kraepelin in the late nineteenth century, originally referring to all kinds of mood disorder. German psychiatrist Karl Leonhard split the classification in 1957, employing the terms unipolar disorder and bipolar disorder.