Major depression - Overview Depression - major; Unipolar
depression; Major depressive disorder Definition of Major
depression: Depression may be described as feeling sad, blue,
unhappy, miserable, or down in the dumps. Most of us feel this
way at one time or another for short periods. True clinical
depression is a mood disorder in which feelings of sadness,
loss, anger, or frustration interfere with everyday life for
weeks or longer. Causes, incidence, and risk factors: The exact
cause of depression is not known. Many researchers believe it is
caused by chemical changes in the brain. This may be due to a
problem with your genes, or triggered by certain stressful
events. More likely, it's a combination of both. Some types of
depression run in families. But depression can also occur if you
have no family history of the illness. Anyone can develop
depression, even kids. The following may play a role in
depression: - Alcohol or drug abuse - Certain medical
conditions, including underactive thyroid, cancer, or lon