There are several different types of depression. Often they are distinguished by their prevalent features, duration and severity of symptoms. Most of these kinds of depression are defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM), an American Psychiatric Association publication which describes the standard criteria for different types of psychiatric disorders.

The following three different kinds of depression are distinct depressive disorders described in the DSM. A common criteria is that their symptoms either cause 1) significant distress or 2) impair one¡¯s functioning (e.g. work, school, relationships). Also, these depressive symptoms are not caused by a medical condition or substance (e.g. medication, drug).

Major Depressive Disorder (also known as Major Depression, Clinical Depression) ¨C A major depressive episode occurs with symptoms that last for most of the day, nearly every day for at least two weeks. A symptom must either be 1) depressed mood or 2) a noticeable decrease in interest or pleasure in all or most activities. At least four (or more) additional symptoms are present:

1.significant weight loss  weight gain or decrease increase in appetite

2.difficulty sleeping or increase in sleeping

3.excessive movement or slowing down associated with mental tension (observed by others)

4.fatigue or loss of energy

5.feeling worthless or excessive guilt

6.difficulty thinking, concentrating or making decisions

7.repeatedly thinking about death or suicide, trying to attempt suicide or having a specific plan to commit suicide

Dysthymic Disorder (or also referred to as Dysthymia) ¨C Nearly constant depressed mood for at least 2 years accompanied by at least two (or more) of the following:

1.decrease or increase in eating

2.difficulty sleeping or increase in sleeping

3.low energy or fatigue

4.low self-esteem

5.difficulty concentrating or making decisions

6.feeling hopeless

Symptoms do not occur for more than two months at a time. Generally, this type of depression is described as having persistent but less severe depressive symptoms than Major Depression.

Manic Depression (now known as Bipolar Disorder) ¨C This kind of depression includes periods of mania and depression. Cycling between these two states can be rapid or only mania can be present without any depressive episodes. A manic episode consists of a persistent elevated or irritable mood that is extreme, which lasts for at least one week. At least three (four if only irritable mood) other features are also present:

1.inflated self-esteem or self-importance

2.decreased need for sleep

3.more talkative than usual or compelled to keep talking

4.experiencing racing thoughts or ideas

5.easily distracted

6.increase in goal-oriented activity (social, work, school, sexual) or excessive movement

7.excessive involvement in potentially risky pleasurable behavior (e.g. over spending, careless sexual activity, unwise business investments)

Symptoms can be severe enough to warrant hospitalization to prevent harm to self or others or include psychotic features (e.g. hallucinations, delusions).

Other Types of Depressive Categories

Post Partum Depression  Major depressive episode that occurs after having a baby. Depressive symptoms usually begin within four weeks of giving birth and can vary in intensity and duration.

Seasonal Affective Disorder (SAD)  A type of depressive disorder which is characterized by episodes of major depression which reoccur at a specific time of the year (e.g. fall, winter). In the past two years, depressive periods occur at least two times without any episodes that occur at a different time.

Anxiety Depression  Not an official depression type (as defined by the DSM). However, anxiety often also occurs with depression. In this case, a depressed individual may also experience anxiety symptoms (e.g. panic attacks) or an anxiety disorder (e.g. PTSD, panic disorder, social phobia, generalized anxiety disorder).

Atypical Depression (Sub-type of Major Depression or Dysthymia) - Characterized by a temporary improvement in mood in reaction to positive events and two (or more) of the following:

1.significant weight gain or increase in appetite

2.over sleeping

3.heavy feeling in arms or legs

4.long standing pattern of sensitivity to rejection

Chronic Depression  Major depressive episode that lasts for at least two years.

Double Depression  Someone who has Dysthymia (chronic mild depression) and also experiences a major depressive episode (more severe depressive symptoms lasting at least two weeks). See above for definitions of these two categories of depression.

Endogenous Depression  Endogenous means from within the body. This type of depression is defined as feeling depressed for no apparent reason.

Situational Depression or Reactive Depression (also known as Adjustment Disorder with Depressed Mood) ¨C Depressive symptoms developing in response to a specific stressful situation or event (e.g. job loss, relationship ending). These symptoms occur within 3 months of the stressor and lasts no longer than 6 months after the stressor (or its consequences) has ended. Depression symptoms cause significant distress or impairs usual functioning (e.g. relationships, work, school) and do not meet the criteria for major depressive disorder.

Agitated Depression Kind of major depressive disorder which is characterized by agitation such as physical and emotional restlessness, irritability and insomnia, which is the opposite of many depressed individuals who have low energy and feel slowed down physically and mentally.

Psychotic Depression  Major depressive episode with psychotic symptoms such as hallucinations (e.g. hearing voices), delusions (false beliefs).

Melancholic Depression (Sub-type of Major Depressive Disorder) - Main features of this kind of depression include either a loss of pleasure in virtually all activities or mood does not temporarily improve in response to a positive event. Also, three (or more) of the following are present:
 
1.Depressed mood that has a distinct quality (e.g. different from feeling depressed when grieving)

2.Depression is consistently worse in the morning

3.Waking up earlier than usual (at last 2 hours)

4.Noticeable excessive movement or slowing down

5.Significant decrease in appetite or weight loss

6.Feeling excessive or inappropriate guilt

Catatonic Depression (Sub-type of Major Depressive Disorder) ¨C This type of depression is characterized by at least two of the following:

1.Loss of voluntary movement and inability to react to one's environment

2.Excessive movement (purposeless and not in response to one's environment)

3.Extreme resistance to instructions/suggestions or unable/unwilling to speak

4.Odd or inappropriate voluntary movements or postures (e.g. repetitive movements, bizarre mannerisms or facial expressions)

5.Involuntarily repeating someone¡¯s words or movements in a meaningless way