What Is Bipolar Disorder?

Bipolar disorder is a serious mental illness that affects millions of Americans each year. If untreated, the disease can produce dramatic mood swings—and can seriously disrupt a person's life and the lives of those around them. While most people have their share of ups and downs, people with bipolar disorder experience a vicious cycle of dangerous highs called "mania" and debilitating lows known as "depression."

The 2 "Poles" of Bipolar

In bipolar disorder, the periods of highs and lows are called manic and depressive "episodes." During manic episodes, your mood soars and your mind races. You may go days without sleep, and you can vastly overestimate your abilities. In periods of depression, just getting out of bed can feel like climbing Mount Everest. You may have difficulty concentrating, and you may lose interest in all your favorite activities. Some people also experience what's known as a "mixed episode," where symptoms of depression accompany the mania.

The length of an episode often differs for each person, and the pattern can change over time. Sometimes an episode will last a few hours or days; other times, it can go on for weeks or even months. In between these episodes, most people with bipolar disorder have a relatively normal period (what doctors call "euthymia"). A series of 4 or more manic or depressive episodes in 12 months is known as "rapid cycling," a condition that can be more difficult to treat.

How Doctors Define Bipolar Disorder

Doctors have identified 4 different forms of bipolar disorder:

Bipolar I disorder—Recurring manic episodes or mixed episodes, and often one or more episodes of depression
Bipolar II disorder—Depression that alternates with a milder form of mania called "hypomania"
Cyclothymic disorder—Moods that shift between short periods of mild mania and mild depression. (Many people with cyclothymia may later develop a more severe form of bipolar illness)
Bipolar disorder not otherwise specified (NOS)—Any form of the illness that doesn't fit the above definitions (eg, recurring hypomania with no depressive symptoms)

Talk to Your Doctor

If you have additional questions or concerns about this topic, talk to your doctor.