Bipolar disorder, also known as manic-depressive illness, is a mental health condition characterized by extreme shifts in mood, energy, and activity levels. The condition is marked by episodes of mania or hypomania (elevated, expansive or irritable mood, increased energy and activity levels, racing thoughts) and depression (persistent low mood, loss of interest, feelings of hopelessness, sleep and appetite changes) that can vary in duration and intensity.

The exact cause of bipolar disorder is not fully understood, but it is believed to be caused by a combination of genetic, environmental, and biological factors. Certain factors, such as a family history of bipolar disorder, can increase the risk of developing the condition.

Treatment for bipolar disorder usually involves a combination of medication, psychotherapy, and lifestyle changes. Mood stabilizers such as lithium, antipsychotics, and anticonvulsants are commonly used to manage bipolar disorder symptoms.