Bipolar disorder is a mental health condition characterized by severe mood swings between depression and elation or mania. These are known as cycles. There are four types of bipolar disorders: bipolar I disorder, bipolar II disorder, cyclothymic disorder, and bipolar disorder due to substance/medication or another medical condition. In addition, there are atypical bipolar conditions that fall into the diagnostic categories of “other specified bipolar and related disorder” and “unspecified bipolar and related disorder.”

What is Bipolar I Disorder?

Bipolar I disorder is marked by “manic episodes” which are distinct periods of elevated, expansive, or irritable mood, with increased goal-directed activity or energy, lasting at least 7 days.

Manic Episodes

A manic episode is severe enough to cause impairment in social or occupational functioning, require hospitalization to prevent harm to self or others, or result in psychotic features. For a bipolar diagnosis, the manic episode cannot be attributable to the physiological effects of a substance (e.g., drug of abuse or medication).

During the manic period, three or more of the following symptoms are present for most of the day (four if the patient’s mood is only irritable):

• Inflated self-esteem or grandiosity
• Decreased need for sleep
• More talkative than usual or pressured to keep talking
• Having a flight of ideas or the feeling that one’s thoughts are racing
• High distractibility to unimportant or irrelevant external stimuli
• Increase in goal-directed activity (socially, at work or school, or sexually) or psychomotor agitation (purposeless non-goal-directed activity)
• Excessive involvement in activities that have a high potential for painful consequences (such as unrestrained buying sprees, sexual indiscretions, or foolish business investments)

A bipolar I diagnosis requires at least one lifetime manic episode.

Hypomanic Episodes

A person with bipolar I disorder may also have “hypomanic episodes.” Hypomanic episodes have all the symptoms of manic episodes and are associated with an uncharacteristic change in behavior but are not severe enough to cause marked impairment in social or occupational functioning or to require hospitalization. A hypomanic episode lasts for 4 consecutive days or more.

Depression

Episodes of major depression are common in bipolar I disorder but are not required for a bipolar I diagnosis. Symptoms of major depression include a depressed mood for most of the day, nearly every day, a loss of interest in pleasure and activities, significant weight loss or weight gain, insomnia or sleeping too much, fatigue, feelings of worthlessness or excessive guilt, diminished ability to think or concentrate, or recurrent thoughts of death or suicide.

How many people are affected by Bipolar Disorders?

The lifetime prevalence of bipolar disorders is thought to be less than 1 percent of the population. However, it can be difficult to estimate because milder forms of bipolar disorder are often not diagnosed.