A constellation of emotional, cognitive and somatic signs and symptoms, including sustained sad mood or lack of pleasure.
Depression is a mood disorder that causes a persistent feeling of sadness and loss of interest. Also called major depressive disorder or clinical depression, it affects how you feel, think and behave and can lead to a variety of emotional and physical problems. You may have trouble doing normal day-to-day activities, and sometimes you may feel as if life isn't worth living. More than just a bout of the blues, depression isn't a weakness and you can't simply "snap out" of it. Without treatment, symptoms can last for weeks, months, or years. Depressive disorders come in different forms, from Seasonal Depressive Disorder to Bipolar disorder. However, within these types there are variations in the number of symptoms as well as their severity and persistence. Depression is a common but serious illness, and most people who experience it need treatment to get better. But don't get discouraged. Most people with depression feel better with medication, psychotherapy or both.