What is bipolar disorder?
Bipolar disorder is a serious mental illness that causes dramatic mood swings for 5.7 million American adults (2.6 percent of the population).  People diagnosed with bipolar, also known as "manic-depressive illness", cycle from energetic highs and/or irritable moods, to sad and hopeless moods ... and then back again. The high feeling is called mania. The down feeling is called depression.  Between these cycles of extreme moods, people with bipolar experience normal moods in between.

Types of bipolar disorder

Bipolar I disorder – Bipolar I is diagnosed for people who experience at least one manic episode, with or without previous episodes of depression.  BP I is considered the classic form of the illness, which involves recurrent episodes of mania and depression.

Bipolar II disorder – Bipolar II is diagnosed for people who experience at least one episode of depression and at least one hypomanic episode. During bipolar II disorder, the periods of depression are typically much longer than the periods of hypomania.

Cyclothymia - Cyclothymia is a mild form of bipolar disorder. Cyclothymia includes mood swings but the highs and lows are not as severe as those of full-blown bipolar disorder.

Mixed state bipolar disorder – During mixed state bipolar, symptoms of both mania and depression occur at the same time.

Rapid cycling bipolar disorder – A person is diagnosed with rapid cycle bipolar when four or more episodes of illness occur within a 12-month period. Some people experience multiple episodes within a single week, or even within a single day. Rapid cycling tends to develop later in the course of illness and is more common among women than among men.

Can anyone be bipolar?  Or are some people more at risk of being diagnosed with bipolar disorder than others?  Read on for more on risk factors for developing biploar disease in the next section on causes and risk factors for bipolar disorder.