There are several forms of depressive disorders. The most common are major depressive disorder and dysthymic disorder.
Major depressive disorder (Major Depression)
- Characterized by a combination of symptoms that interfere with a person's ability to work, sleep, study, eat, and enjoy once–pleasurable activities.
- Disabling and prevents a person from functioning normally.
- An episode of major depression may occur only once in a person's lifetime, but usually recurs throughout a person's life.
Dysthymic disorder (Dysthymia)
- Characterized by less severe symptoms over a two-year or longer period that may not disable a person but can prevent one from functioning normally or feeling well.
- People with dysthymia may also experience one or more episodes of major depression during their lifetimes.
Psychotic depression
- Severe depressive illness is accompanied by some form of psychosis, such as a break with reality, hallucinations, and delusions.
Postpartum depression
- New mother develops a major depressive episode within one month after delivery.
Seasonal affective disorder (SAD)
- Characterized by the onset of a depressive illness during the winter months, when there is less natural sunlight.
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