Bipolar disorder

John Hammond MD (

Dr. Hammond of the University of Alabama at Birmingham has no relevant financial relationships to disclose.

David S Geldmacher MD (

Dr. Geldmacher, Director of the Division of Memory Disorders and Behavioral Neurology at the University of Alabama at Birmingham, received research grants from Abbvie, Biogen, BristolMyersSquibb, Eisai, Janssen, Lilly, Lundbeck, and Neurim Pharmaceuticals, and consultation fees from Axovant, Grifols, and GlaxoSmithKline.

Victor W Mark MD, editor. (Dr. Mark of the University of Alabama at Birmingham has no relevant financial relationships to disclose.)
Originally released April 20, 2019; expires April 20, 2022

This article includes discussion of bipolar disorder, manic depression, bipolar type I, and bipolar type II. The foregoing terms may include synonyms, similar disorders, variations in usage, and abbreviations.


Bipolar disorder, or manic depression, is a serious mental illness that may drastically affect an individual s ability to function because of mood instability. Given the unpredictability of severe high (mania) and severe low (depression) mood states, people with bipolar disorder may struggle with social and workplace settings. Bipolar disorder affects mood, sleep, concentration, and reasoning. Some individuals may experience psychosis or may struggle with suicidal thoughts. Although the underlying cause of bipolar disorder is not clear, research in neurobiology and genetics provides some insight into this complex illness. Treatment of the disorder is primarily with mood stabilizers, but often requires additional adjunctive medications. Additionally, psychosocial support and therapy are essential for maintaining stability. This article aims to provide distinction between bipolar disorder subtypes and includes updates on the current research regarding the underlying pathology as well as guidance on the pharmacologic treatment of the illness.

Key points


• Bipolar disorder may be diagnosed after a single manic episode.


• Patients will often experience a combination of depressive, manic, and hypomanic episodes throughout the course of illness.


• The severity and frequency of mood symptoms vary among individuals.


• The role of treatment is to stabilize mood and decrease the severity and frequency of mood episodes.

Historical note and terminology

Manic depression was first noted by ancient Greek scholars, including Hippocrates, and the term “mania” is derived from the Greek word for “madness” (Crocq 2015). The idea of a madness related to one s mood persisted until near the end of the 19th century when Emil Kraeplin distinguished between manic-depressive psychosis and dementia praecox (modern schizophrenia) (Zivanovic and Nedic 2012). The idea of an illness with 2 distinct affective poles, mania and depression, was introduced by Karl Leonhard in the 1950s (Lopez-Munoz et al 2018). Today, bipolar disorder is recognized as a serious mental illness within the Diagnostic and Statistical Manual of Mental Disorders.

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