Are there different types of depression?

In the past, depression was divided into two types. Reactive or exogenous depression was the term used to describe depression that was caused by an easily identifiable trigger such as losing your job. Biological or endogenous depression was used for depression that developed out of the blue. However, such a classification has fallen out of favor for a number of reasons. Firstly, it does not seem to matter whether there is an obvious reason for the depression or not; sufferers still respond to the same treatment. And, secondly, there is growing recognition that both internal and external factors play a role in the development of depression in most people.

Usually, Depression is further divided according to level of overall severity

Mild depression is often self–limiting and may respond to additional support and help. Even so it cannot be dismissed lightly, as without treatment, it may develop into moderate Depression

Moderate depression presents with a wider range of symptoms and difficulty in functioning at home or at work.

Severe depression is a serious illness. It causes great and comprehensive distress in all areas of functioning, and is most likely to be associated with suicidal thoughts.

But in addition to these broad categories there are a number of other types of depressions recognized.

Depression can be further defined as unipolar or bipolar. In unipolar depression people may suffer from repeated episodes of depression. However, their mood returns to normal at the end of an episode, is characterized by alternating periods of depression and mania, where the person has an exaggerated sense of well being which may make him/her very reckless. This type of illness is also referred to bipolar disorder.

Dysthymia is the name given to an illness in which the symptoms are similar but much milder than those of major depression. It is also characterized by a prolonged course.

Psychotic depression is characterized by psychotic features such as delusions or hallucinations. Lastly, there are a number of specific syndromes. These include seasonal affective disorder (SAD) and post partum depression.

Sad usually occurs only in winter and may be due to a lack of sunlight. One of the most effective treatments appears to be exposure to artificial light.

Post partum depression affects mothers usually within six weeks of the birth of a child. A more severe, but rare form, is puerperal psychosis which has symptoms similar to manic depression and often requires admission to hospital.

What is an antidepressant?

It is perhaps more difficult to specify exactly what antidepressants do than any other drugs that act on the brain. But to go back to our analogy between mood and emotions and climate and the weather, antidepressants reset climate controls rather than acting on a particular piece of bad weather. This means antidepressants do not act immediately. The lifting of depressed moods typically takes up to two weeks and can take longer. This is in contrast to other drugs which work on the brain like, for example, tranquillizers which give you an immediate and usually very obvious hit.

There are two other unique features about antidepressants, which distinguish them from other chemicals which act on the brain:

Cognitive behavioral therapy is a short term (usually about ten week) structured psychotherapy which aims to help the depressed person replace negative thoughts and attitudes with a more realistic view of themselves and the world about them.

Interpersonal psychotherapy focuses more on past and present relationship and examines how they affect the patient’s current functioning.

Antidepressants
Antidepressant therapies began in 1956 when a drug used in the treatment of tuberculosis was found to elevate mood. Two years later, the antidepressant Imipramine was discovered. It provided the first scientifically proven treatment for depression and demonstrated that depression was amenable to medical intervention. Now there is a wide choice of antidepressants available. There are the recognized treatment for all forms of moderate and severe depression regardless of cause. About 70 per cent of patients with depression respond to treatment with antidepressants.

Antidepressants are useful and effective. They are not addictive and do not lose efficacy with continued use. They can be distinguished most commonly by their safety profile or tolerability, although there are indications that efficacy, especially in severe depression, varies between classes of antidepressants.

Many drugs which act on the brain have much the same action on people who are unaffected by mental illness or those who have a problem. By contrast, antidepressants only seem to do something to people who are depressed. They don’t seem to make someone who is not depressed different in any other way.

The effect of antidepressants does not increase the greater the dose you use. Dr. D. Healy in his book ‘Psychiatric Drugs Explained’ (Mosby 1997) explains effects of antidepressants using comparison with coffee or alcohol intake. One cup of coffee may be alerting, two cups more so and three cups make you really wired up. Similarly, the more you drink, the greater the effect that alcohol has on the brain. But with antidepressants taking a dose.