Bipolar disorder is a mental health condition marked by extreme swings in mood, energy, and the ability to function. The mood changes of bipolar disorder are more dramatic than normal ups and downs. They can hurt relationships and cause poor job or school performance.

The two mood extremes of bipolar disorder are mania and depression. In mania, one of the defining symptoms is an increase in energy and a decreased need for sleep. The mood may be overly happy or irritable. In depression, a down mood with fatigue takes over, often accompanied by irritability.

There are four forms of this condition:

  • Bipolar I disorder—Recurrent episodes of mania often immediately followed by depression; episodes can be severe.
  • Bipolar II disorder—Episodes of less severe mania (called hypomania) that alternate with episodes of major depression.
  • Bipolar disorder not otherwise specified (BP-NOS)—The person has symptoms of bipolar disorder, but the symptoms do meet the specific criteria for bipolar I or bipolar II disorder
  • Cyclothymia—Episodes of hypomania that alternate with episodes of mild depression that last for at least two years

The cause of bipolar disorder is unknown. This condition tends to run in families. Specific genes may play a role. It is most likely many different genes that act together.

The Brain
Color coded brain
Bipolar disorder may be a result of genetic influences on the brain.
Copyright © Nucleus Medical Media, Inc.