Bipolar disorder, (formerly known as manic-depressive illness or manic depression) is a mental health condition that causes extreme mood swings that include emotional highs (mania or hypomania) and lows (depression).

When you become depressed, you may feel sad, emptiness or hopeless and lose interest or pleasure in most activities. When your mood shifts to mania or hypomania (less extreme than mania), you may feel euphoric, full of energy or unusually irritable. These mood swings can affect sleep, energy, judgment, activity, behavior and the ability to think clearly.

Episodes of mood swings may occur multiple times or rarely in a year. While most people will experience some emotional symptoms between episodes and some may not.