Bipolar disorder (formerly called manic-depressive illness or manic depression) is a mental illness that causes clear shifts in a person’s mood, energy, activity levels, and concentration. People with bipolar disorder often experience periods of extremely “up,” elated, irritable, or energized behavior (known as manic episodes) and very “down,” sad, indifferent, or hopeless periods (known as depressive episodes).

The symptoms of bipolar disorder can impose serious challenges to a person’s mental and physical health. People with bipolar disorder often have other mental disorders, and some people may experience symptoms of psychosis, such as hallucinations or delusions. The symptoms can interfere with everyday activities, relationships, and work or school responsibilities. Some people may also experience stigma related to their symptoms, which can keep them from seeking the help they need. Bipolar disorder usually requires lifelong treatment, but an effective treatment plan can help people manage their symptoms and improve their quality of life.