CHARLES DICKENS wrote A Christmas Carol, a story that captures the traditional spirit of Christmas, while he was living at Devonshire Terrace in Marylebone — very near to Harley Street, the long-established haunt of doctors. Dickens, and probably also his father, upon whom Mr Micawber is loosely based, exhibited many of the classic signs of manic depression, now known as bipolar disorder.

If Dickens had lived today and had consulted one of the doctors in his neighbourhood when he was in one of his depressive periods, rather than in a manic phase, the doctor might well have prescribed him, unwisely, an SSRI antidepressant. The result could have been disastrous. The writer’s behaviour was unpredictable, his moods changed rapidly and SSRIs can precipitate manic, violent or self-destructive behaviour.

Dickens, like many creative people with bipolar disorder, was at his most productive during a hypomanic phase when his mania was just under control. He was then full of energy, animated, theatrical, colourful, the life and soul of the party and bursting with ideas. Many creative geniuses have bipolar disorder, and their closest blood relatives often have an average IQ that is ten points higher than normal.

When I went into general practice in Norfolk 40 years ago the first antidepressants had just been introduced, the group known as tricyclics. As a hospital doctor I had been working under Dr Arthur Spencer Paterson, who was one of the early advocates of using both physical and psychotherapeutic methods of treatment. The arrival of these drugs in a rural practice was revolutionary. People who had been confined to their houses for years with severe depression returned to the community, others who had hovered on the brink of suicide became sociable again and, occasionally, went on to become pillars of the community through work with the British Legion or the Women’s Institute. Wives who had been driven to despair by a combination of their situation and a vulnerable personality cancelled their appointments with the divorce lawyers and came to terms with their lives, often very contentedly.

Soon antidepressant drugs had altered general practice and psychiatry for ever. The mental hospitals emptied. Their shrubberies were cut down and the hospitals sold for housing. The treatment of depression was one of the few medical revolutions that started in general practice, and it took place despite the inevitable discouragement of the then Ministry of Health. The authorities were, as usual, anxious about cost. Their GP newsletter explained how the now-reviled barbiturates were better and safer than antidepressants.

So good were the modern antidepressants that they soon became overprescribed. Troubles with antidepressants often seem to arise when they are given, without any other treatment, to patients with bipolar disorder or schizophreniform symptoms. Because these conditions usually first make their appearance in younger people, it is often in this age group that acute problems surface if they are inappropriately treated.

Another group for whom antidepressants can be detrimental is that of people who find change difficult. They find the side-effects of antidepressants so intolerable that they frequently feel worse than they did when bearing their mild depressive feelings.

The recent guidelines on depression and anxiety issued by the National Institute for Clinical Excellence (NICE) suggest that patients with mild depression do not usually need antidepressants and that these drugs are rarely beneficial to them.

The third group to suffer from inappropriate prescription of SSRIs are those who give up their antidepressants suddenly or prematurely. Not only may the patient suffer a clutch of symptoms from the sudden withdrawal of treatment, but any recurrence of the depression may be difficult to treat.

An appreciable percentage of true depressives, possibly as high as 15 per cent, respond to antidepressants but have to take them in the long term. They are not addicted to them but need to take them, just as diabetics need to have insulin regularly, because the underlying biochemical problem is chronic. In both cases, the patients have long-term biochemical abnormalities that need long-term treatment.

NICE recommends the use of SSRIs when an antidepressant is needed. SSRIs replaced the tricylic antidepressants similar to those that I unleashed on my patch in Norfolk in the 1960s. Unfortunately the tricyclics, which are still useful in certain conditions, may occasionally cause serious heart irregularities, and overdoses from them are hard to treat.

NICE did make one specific recommendation in its guidelines. It suggested that Effexor (venlafaxine) should be prescribed only by those with a special knowledge and interest in psychiatry. This does not necessarily mean a consultant psychiatrist. GPs have been prescribing this drug for ten years and if patients are doing well on it, then it should not be discontinued.

All psychiatric care should be carefully monitored. Venlafaxine inhibits two groups of chemicals and is efficacious in some patients who, though no longer clinically depressed, still lack energy.

Recent randomised trials have suggested that venlafaxine does not have any obvious advantage over Cipralex (escitalopram), another recently introduced and effective antidepressant that is widely prescribed.

• www.timesonline.co.uk/health
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