This is the most severe category of depression. In a major depression, more of the symptoms of depression are present, and they are usually more intense or severe. A major depression can result from a single traumatic event in your life, or may develop slowly as a consequence of numerous personal disappointments and life problems. Some people appear to develop the symptoms of a major depression without any obvious life crisis causing it. Other individuals have had less severe symptoms of depression for a long time (such as Dysthymic disorder), and a life crisis results in increased symptom intensity.
Major depression can occur once, as a result of a significant psychological trauma, respond to treatment, and never occur again within your lifetime. This would be a single episode depression. Some people tend to have recurring depression, with episodes of depression followed by periods of several years without depression, followed by another episode, usually in response to another trauma. This would be a recurrent depression. In general, the treatment is similar, except that treatment usually is over a longer time period for recurrent depression.
Professional debate continues regarding whether some people develop "endogenous depression" without any identified psychological causes. An endogenous depression is a biologically caused depression, due presumably to either genetic causes or a malfunction in the brain chemistry. But, all depression involves some changes in brain chemistry, even when the cause is clearly a psychological trauma. After psychological treatment and recovery from depression, the brain chemistry returns to normal, even without medication. To date, there is no hard research evidence to support the notion of endogenous depression. Sometimes this term is used to describe people who do not respond well to treatment, and sometimes it is a rationale to prescribe medication alone, and not to offer any psychological treatment for the depression. In general, the majority of people who require antidepressant medication for their depression respond to treatment better when psychotherapy, particularly cognitive-behavioral psychotherapy, is provided in addition to the medication. Medication treats the symptoms of depression, and is often a vital part of the treatment program, but it is essential to treat the psychological problems that caused the depression.
Research has shown that cognitive therapy is the best treatment for depression, as compared to medication and other forms of psychotherapy. However, many people respond better to a combination of medication and cognitive therapy. It does not make sense to only prescribe medication, without offering psychotherapy as well, because of the added benefits shown in research studies. There are some people who respond positively to psychotherapy, but plateau at a mild level of depression, without complete recovery from all of the symptoms. Often, these individuals are maintained on antidepressant medication after they have completed psychological treatment. Remember, only physicians are qualified to prescribe medication. Your psychologist will refer you to your primary care physician, or to a psychiatrist, for a medication evaluation, if it appears to be indicated.
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