Those who suffer severe forms of depression may be unable to eat or get out of bed. An estimated 15 percent of people hospitalized for depression eventually commit suicide. The causes are not always known. In some cases, symptoms appear suddenly for no apparent reason. In others, the symptoms are clearly connected with a life crisis, stress, or other illness.
Research shows that depressive illnesses run in families.
An accurate diagnosis, including a complete physical examination is needed for treatment to be effective.