What is the medical definition of Major Depressive Disorder?
According to the DSM-IV, a person who suffers from a major depressive disorder must either have a depressed mood or a loss of interest or pleasure in daily activities consistently for at least a two week period. This mood must represent a change from the person’s normal mood; social, occupational, educational or other important functioning must also be negatively impaired by the change in mood. This disorder is characterized by the presence of the majority of these symptoms***: • depressed mood most of the day, nearly every day, as indicated by either subjective report (e.g., feels sad or empty) or observation made by others (e.g., appears tearful). (In children and adolescents, this may be characterized as an irritable mood.) • markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly every day • significant weight loss when not dieting or weight gain (e.g., a change of more than 5% of body weight in a month), or decrease or increase in appetit
