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Definition: depression from Philip's Encyclopedia

Disorder characterized by feelings of guilt, failure, worthlessness or rejection. Frequently a response to a difficult life-situation, depression leads to low self-esteem, self-recrimination and obsessive thoughts. Insomnia, loss of appetite and lethargy are often present, and in severe cases there is a risk of suicide. See also manic depression

Summary Article: Depression
from Black's Medical Dictionary, 42nd Edition

Depression is a word that is regularly misused. Most people experience days or weeks when they feel low and fed up (feelings that may recur), but generally they get over it without needing to seek medical help. This is not clinical depression, best defined as a collection of psychological symptoms including sadness; unhappy thoughts characterised by worry, poor self-image, self-blame, guilt and low self-confidence; downbeat views on the future; and a feeling of hopelessness. Sufferers may consider suicide, and in severe depression may develop HALLUCINATIONS and DELUSIONS.

Doctors make the diagnosis of depression when they believe it is causing a patient to be ill; depression may affect physical health and in some instances be life-threatening. This form of depression is common, with up to 15 per cent of the population suffering from it at any one time, while about 20 per cent of adults have ‘medical’ depression at some time during their lives. It is one of the most common diagnoses in general practice, and one in 6 women and one in 9 men seek medical help for this disorder.

Manic depression is a serious form of the disorder that recurs throughout life and produces bouts of abnormal elation - the manic stage. Both the manic and depressive phases are commonly accompanied by psychotic symptoms such as delusions, hallucinations and a loss of sense of reality. This combination is sometimes termed a manic-depressive psychosis or bipolar affective disorder because of the illness's division into two parts. Another psychiatric description is the catch-all term ‘affective disorder’.


In mild depression, low mood and loss of interest are the main symptoms; the sufferer may cry without any reason or be unresponsive to relatives and friends. In its more severe form, there is a loss of appetite; sleeping problems; lack of interest in and enjoyment of social activities; tiredness for no obvious reason; indifference to sexual activity; and a lack of concentration. The individual's physical and mental activities slow down and he or she may contemplate suicide. Symptoms may vary during the 24 hours, being less troublesome during the latter part of the day and worse at night. Some people get depressed during the winter months, probably a consequence of the long hours of darkness: this disorder - SEASONAL AFFECTIVE DISORDER SYNDROME, or SADS - is thought to be more common in populations living in areas with long winters and limited daylight. Untreated, a person with depressive symptoms may steadily worsen, even withdrawing to bed for much of the time, and allowing his or her personal appearance, hygiene and environment to deteriorate. Children and adolescents may also suffer from depression and the disorder is not always recognised.


A real depressive illness rarely has a single obvious cause, although sometimes the death of a close relative, loss of employment or a broken personal relationship may trigger a bout. Depression probably has a genetic background; for instance, manic depression seems to run in some families. Viral infections sometimes cause depression and hormonal disorders - for example, HYPOTHYROIDISM or postnatal hormonal disturbances (postnatal depression) - may also contribute. Difficult family or social relations can contribute to the development of the disorder.


This depends on the type and severity of the depression.

The National Institute for Health and Clinical Excellence (NICE) recommends that, in mild depression, patients who are likely to get better spontaneously or who do not want intervention should simply be reassessed after a time. Antidepressant drugs are not recommended in this form of the condition. Rather doctors should advise a guided self-help programme based on COGNITIVE BEHAVIOUR THERAPY. Exercise programmes may also help. Short term psychological treatment, such as problem-solving therapy, brief CBT or counselling over about a 3 month period is advised for those with mild and moderate depression who request or need treatment. Antidepressant medication together with CBT may be advised for some in this group, particularly if they do not respond to other procedures, and for all those who present with severe depression. Where patients seem to pose a significant risk to themselves or others, referral to psychiatric services is usual. Antidepressent drugs are divided into three main groups: TRICYCLIC ANTIDEPRESSANT DRUGS (amitriptyline, imipramine and dothiepin are examples); MONOAMINE OXIDASE INHIBITORS (MAOIS) (phenelzine, isocarboxazid and tranyl-cypromine are examples, and in general these should be prescribed only by specialist mental health practitioners and general practitioners with a special interest in mental health); and SELECTIVE SEROTONIN-REUPTAKE INHIBITORS (SSRIS) (fluoxetine - well known as Prozac®, fluvoxamine and paroxetine are examples). In routine care, an SSRI is used first as it is less likely to cause unpleasant side-effects. All patients should be told that if they stop the drug or miss or reduce the dose they may get withdrawal symptoms, usually mild and short-lasting but sometimes severe, especially if the drug is stopped suddenly. Usually treatment is for a relatively brief time, but those who have had two or more episodes in the recent past or whose symptoms have made life particularly difficult may need to continue for as long as two years. There is evidence that St John's Wort might help in mild depression but health-care professionals have been adviced by NICE not to prescribe it because of uncertainty about dose, variety in the strength of different preparations and possible interactions with other drugs, including oral contraceptives, anticoagulants and anticonvulsants. For manic depression, lithium carbonate is the main preventive drug and it is also used for persistent depression that fails to respond to other treatments. Long-term lithium treatment reduces the likelihood of relapse in about 80 per cent of manic depressives, but the margin between control and toxic side-effects is narrow, so the drug must be carefully supervised. Indeed, all drug treatment for depression needs regular monitoring as the substances have powerful chemical properties with consequential side-effects in some people. Furthermore, the nature of the illness means that some sufferers forget or do not want to take the medication.

Some patients with depression - particularly those with manic depression or who are a danger to themselves or to the public, or who are suicidal - may need admission to hospital, or in severe cases to a secure unit, in order to initiate treatment. But as far as possible patients are treated in the community (see MENTAL ILLNESS).

If drug treatments fail, severely depressed patients may be considered for ELECTROCONVULSIVE THERAPY (ECT). This treatment has been used for many years but is now only rarely recommended, basically to achieve rapid and short-term improvement of severe symptoms after other treatment has failed or if the condition is considered likely to be life-threatening. Given under general anaesthetic, in appropriate circumstances, ECT is safe and effective, though temporary impairment of memory may occur. Because the treatment was often misused in the past, it still carries a reputation that worries patients and relatives; hence careful assessment and counselling are essential and consent from the patient should be obtained without pressure or coercion and after a full discussion.

Copyright © A & C Black Publishers Ltd

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