ARTICLE

Bipolar affective disorder is a chronic enduring mental illness characterised by periods of elation and depression in mood. The modern conceptualisation of this phenomenon as a distinct illness dates back to the 19th century when Falret first described the concept of folie circulaire. By the start of the 20th century, Kraepelin had coined the term manic depressive psychosis and unified the classification of affective disorders into manic depressive illnesses, which also included unipolar depressive episodes. The unipolar/bipolar distinction was formally introduced into diagnostic classifications in 1980 with the publication of DSM–III and has been carried forward into DSM–IV–TR. This gives a descriptive definitio