Specialty Behavioral Health

Types of Depressive Disorders

Major Depressive Disorder (MDD)

A period of at least 2 weeks with a significant change in mood marked by feeling sad, empty, or anxious; loss of interest or pleasure in life; decreased energy, sex drive, or sleep; changes in appetite or body weight; mental dullness or diminished concentration; or morbid thoughts. Often triggered by a significant event, but sometimes occurs seemingly for no reason.


A chronic pattern of mild depression (with some or all of symptoms of MDD) occurring for more days than not for at least 2 years. It is often characterized by pessimism, feeling easily overwhelmed or frustrated, or disappointment.

Bipolar Disorder

Extreme changes in mood resulting in both periods of depression and mania. Mania is characterized by elevated, irritable, or grandiose mood; racing thoughts; increased energy or activity; risky behaviors and poor judgment. Often, people are unaware of being in a manic state.

Adjustment Disorder

Emotional difficulties related to a significant life event such as a relationship or legal problem. It can include symptoms of depression that interfere with the ability to function fully for a significant period of time.

Grief Reaction

Although a grief reaction to a major loss is not technically a type of clinical depression, it can include many similar symptoms and professional treatment is sometimes warranted.

Clinical depression can also be caused by medical conditions and substances (including alcohol, drugs and prescribed medications). These types of depression are also treatable. For more information about depression and free publications from the NIMH, click here.