This article is from the Depression FAQ, by Cynthia Frazier with numerous contributions by others.
Depression comes in many forms and in many degrees. Below, you will find some of the most common depressive types, along with some of the diagnostic criteria from the DSM-III-R (the official diagnostic and statistical manual for psychiatric illnesses).
**Major Depression:** This is a most serious type of depression. Many people with a major depression can not continue to function normally. The treatments for this are medication, psychotherapy and, in extreme cases, electroconvulsive therapy (ECT).
A. At least five of the following symptoms have been present during the same two-week period and represent a change from previous functioning; at least one of the symptoms is either (1) depressed mood, or (2) loss of interest or pleasure. (Do not include symptoms that are clearly due to a physical condition, mood- incongruent delusions or hallucinations, incoherence, or marked loosening of associations.)
1. depressed mood most of the day, nearly every day, as indicated either by subjective account or observation by others
2. markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly every day (as indicated either by subjective account or observation by others of apathy most of the time)
3. significant weight loss or weight gain when not dieting (e.g. more than 5% of body weight in a month), or decrease or increase in appetite nearly every day
4. insomnia or hypersomnia nearly every day
5. psychomotor agitation or retardation nearly every day (observable by others, not merely subjective feelings of restlessness or being slowed down)
6. fatigue or loss of energy nearly every day
7. feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) nearly every day (not merely self- reproach or guilt about being sick)
8. diminished ability to think or concentrate, or indecisiveness nearly every day (either by subjective account or as observed by others)
9. recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, or a suicide attempt or a specific plan for committing suicide
B. (1) It cannot be established that an organic factor initiated and maintained the disturbance (2) The disturbance is not a normal reaction to the death of a loved one
C. At no time during the disturbance have there been delusions or hallucinations for as long as two weeks in the absence of prominent mood symptoms (i.e..- before the mood symptoms developed or after they have remitted).
D. Not superimposed on Schizophrenia, Schizophreniform Disorder, Delusional Disorder, or Psychotic Disorder
**Dysthymia:** This is a mild, chronic depression which lasts for two years or longer. Most people with this disorder continue to function at work or school but often with the feeling that they are "just going through the motions." The person may not realize that they are depressed. Anti-depressants or psychotherapy can help.
A. Depressed mood (or can be irritable mood in children and adolescents) for most of the day, more days than not, as indicated either by subjective account or observation by others, for at least two years (one year for children and adolescents)
B. Presence, while depressed, of at least two of the following:
1. poor appetite or overeating
2. insomnia or hypersomnia
3. low energy or fatigue
4. low self-esteem
5. poor concentration or difficult making decisions
6. feelings of hopelessness
C. During a two-year period (one-year for children and adolescents) of the disturbance, never without the symptoms in A for more than two months at a time.
D. No evidence of an unequivocal Major Depressive Episode during the first two years (one year for children and adolescents) of the disturbance.
E. Has never had a Manic Episode or an unequivocal Hypo manic Episode.
F. Not superimposed on a chronic psychotic disorder, such as Schizophrenia or Delusional Disorder.
G. It cannot be established that an organic factor initiated or maintained the disturbance, e.g., prolonged administration of an antihypertensive medication.
**Adjustment Disorder with Depressed Mood:** This is the type of depression that results when a person has something bad happen to them that depresses them. For example, loss of one's job can cause this type of depression. It generally fades as time passes and the person gets over what ever it was that happened.
A. A reaction to an identifiable psycho social stressor (or multiple stressors) that occurs within three months of onset of the stressor(s).
B. The maladaptive nature of the reaction is indicated by either of the following:
1. impairment in occupational (including school) functioning or in usual social activities or relationships with others
2. symptoms that are in excess of a normal and expectable reaction to the stressor(s)
C. The disturbance is not merely one instance of a pattern of overreaction to stress or an exacerbation of one of the mental disorders previously described (in the entire DSM).
D. The maladaptive reaction has persisted for no longer than six months.
E. The disturbance does not meet criteria for any specific mental disorder and does nor represent Uncomplicated Bereavement.