health

Depression, sometimes called major depression or depressive disorder, is
a mood disorder that has been called the “common cold of mental illness”
because it is so common in the general population. Unlike the
common cold, however, depression can have serious long-term effects
on a person’s quality of life.

Some types of depression are recognized as separate disorders:

• Dysthymia. Also called dysthymic disorder, dysthymia is a condition
  in which the person has milder symptoms of depression that
  are less disabling than those of major depression over a period of
  two years or longer.
  
• Psychotic depression. Patients with this type of depression have
  hallucinations, delusions, and other signs that they have lost contact
  with reality.
  
• Postpartum depression. This is a type of depression that affects
  some women following the birth of a baby.
• Seasonal affective disorder (SAD). SAD is a form of depression
  related to changes in the seasons. Most people with SAD feel
  depressed in the winter and better in summer, but there is also a
  reverse form of SAD in which the person is depressed in summer
  and feels better in winter.