What is Bipolar Disorder (Manic Depression)

If you picture a globe, the North Pole would be mania, and the South Pole would be depression.

Full description of Bipolar Disorder. Types of Bipolar Disorder plus signs, symptoms and causes of Bipolar Disorder.

Description of Bipolar Disorder

Bipolar disorder (also known as manic depression) is a treatable illness and can affect a person's ability to experience a normal range of mood. It is marked by extreme changes in mood, thought, energy and behavior. It is not a character flaw or a sign of personal weakness.

Bipolar disorder affects more than two million adult Americans. It usually begins in late adolescence (often appearing as depression during teen years) although it can start in early childhood or later in life. An equal number of men and women develop this illness (men tend to begin with a manic episode, women with a depressive episode) and it is found among all ages, races, ethnic groups and social classes. The illness tends to run in families and appears to have a genetic link. Like depression and other serious illnesses, bipolar disorder can also negatively affect spouses and partners, family members, friends and coworkers.

Bipolar disorder is also known as manic depression because a person's mood can alternate between the "poles" - mania (highs) and depression (lows). This change in mood can last for hours, days, weeks or months. Every time you experience symptoms at one pole for at least 1 week, it is called an episode. Experiencing 4 or more episodes of mania and/or depression in a year is called rapid-cycling bipolar disorder.

While mood changes with bipolar disorder typically occur gradually, with bipolar rapid cycling, a full cycle can be completed within days (some individuals even complete a cycle in hours). This pattern of rapid cycling is seen in approximately 5 to 15 percent of patients with bipolar disorder and tends to develop late in the disorder. Because those who rapid-cycle represent a moving target so-to-speak, and because of the instability of their condition, this group of people are notoriously difficult to treat, with high rates of failure. Women are more likely than men to be rapid-cyclers.

Types of Mood Episodes Associated With Bipolar Disorder

  • Manic Episode (Maniais a distinct period during which there is an abnormally and constantly elevated, expansive, or irritable mood, lasting at least 1 week.

  • Hypomanic Episode (Hypomania) is a milder form of mania that lasts at least 4 days.

  • Major Depressive Episode (Depression) is a period during which there is either depressed mood or the loss of interest or pleasure in nearly all activities, lasting for at least 2 weeks.

  • Mixed Episode is a period of time during which a person experiences both manic and major depressive symptoms nearly every day for at least 1 week.

Types of Bipolar Disorder

Patterns and severity of symptoms, or episodes, of highs and lows, determine different types of bipolar disorder.

  • Bipolar I disorder is characterized by one or more manic episodes or mixed episodes (symptoms of both a mania and a depression occurring nearly every day for at least 1 week) and one or more major depressive episodes. Bipolar I disorder is the most severe form of the illness marked by extreme manic episodes.

  • Bipolar II disorder is characterized by one or more depressive episodes accompanied by at least one hypomanic episode. Hypomanic episodes have symptoms similar to manic episodes but are less severe, but must be clearly different from a person's non-depressed mood. For some, hypomanic episodes are not severe enough to cause notable problems in social activities or work. However, for others, they can be troublesome.

  • Cyclothymic disorder is characterized by chronic fluctuating moods involving periods of hypomania and depression. The periods of both depressive and hypomanic symptoms are shorter, less severe, and do not occur with regularity as experienced with bipolar II or I. However, these mood swings can impair social interactions and work. Many, but not all, people with cyclothymia develop a more severe form of bipolar illness.

  • Bipolar Disorder Not Otherwise Specified (NOS)
    When the bipolar disorder is not characterized by any of the above mentioned types of bipolar disorder.1 The experiences of bipolar disorder vary from person to person. Occasionally someone will experience the symptoms of a manic episode and a major depressive episode, but not fit into the above mentioned types of bipolar disorder. This is known as Bipolar Disorder Not Otherwise Specified. Just like the other types of bipolar disorder, Bipolar Disorder Not Otherwise Specified is a treatable disorder.

Causes of Bipolar Disorder

Full description of Bipolar Disorder. Types of Bipolar Disorder plus signs, symptoms and causes of Bipolar Disorder.

The exact cause of bipolar disorder is not known, but researchers believe a combination of factors may play a role in developing bipolar disorder. These include a brain chemical imbalance (an imbalance in the level of the neurotransmitters such as serotonin or norepinephrine) and genetics. There is a strong genetic component to bipolar disorder. If a family member has bipolar disorder, other family members may be at risk.

Sometimes a period of emotional stress, drug use, an illness, or another event seems to trigger the onset of the bipolar disorder. Stresses can also trigger a manic or depressive episode in people who are known to have the condition.

For comprehensive information on bipolar and other mood disorders, visit the Bipolar Community.


1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th Ed. Text Revision. Washington, DC: American Psychiatric Association; 2000.

2. Depression and Bipolar Support Alliance. Guide to Depression and Manic-Depression [brochure]. Chicago, Ill: Depression and Bipolar Support Alliance; 2001.

APA Reference
Staff, H. (2009, January 2). What is Bipolar Disorder (Manic Depression), HealthyPlace. Retrieved on 2020, June 1 from

Last Updated: July 3, 2019

Medically reviewed by Harry Croft, MD

More Info