'I'm glad to be a Seroxat addict'

I am convinced that antidepressants are life-savers, and I don't believe that simply because of my own experience. Yet there is still a great deal of hostility to taking these drugs, and there have been some wild accusations as to what effects they may have.

Recent headlines have referred to them as being responsible for turning children into killers and driving mums to suicide. There are also claims that the drugs are addictive and that the marketing of them is devious and dishonest. But I'm not sure how good the evidence is for these accusations.

There is almost a conspiracy to blame such drugs for causing terrible mental damage and to discourage their use. In fact, they are usually lifesaving. Even psychiatrists who are depressed take them.

Seven years ago, at the age of 64, I had my first attack of depression - the worst experience of my life. It was set off by anxiety about a minor heart problem, but the result was terrifying. When one is seriously depressed - I do not mean feeling very low or sad - one enters a state that is indescribable. I entered a world that bore no relation to anything I knew. I now maintain that if you can describe your depression, you have not had it. It is no coincidence that an illness affecting about one in 10 of the population has never been successfully described in any English novel.

I was suicidal and hospitalised. About 10 per cent of severe depressives attempt suicide; many are successful. My psychiatrist put me on Seroxat, and when I asked her why she had chosen that particular antidepressant, she said that, in her experience, patients suffered the fewest side-effects and seldom had to be taken off it. I very slowly began to recover - it took several weeks in hospital and another month at home before I could consider returning to work. It was a great strain on my family as, like all depressives, I was totally negative and self-involved. I was happily married and a professor at the university, I had no serious illness, yet only wished to lie in bed and think of death. My wife could not understand my condition. With the help of cognitive therapy, I recovered and came off Seroxat.

But four years later I had another depressive episode, possibly triggered by my fear of retirement from my job as professor of medical biology at University College London. I went back on Seroxat and managed to continue working with very great difficulty. I remained on the drug, but on a very low dose, for about a year, and then last year the depression returned. This time I did not feel depressed but nauseous and ill. My psychiatrist was sure I was depressed and expressing it in physical symptoms. After four months on Seroxat, I recovered and now take a low dose daily. At present, I am doing very well and am often asked if the Seroxat is working.

I cannot tell, but I do not intend to try to find out by stopping taking it. Yes, it does affect my sex life, which is a well known side-effect, but, for me, the benefits outweigh such problems.

Depression is usually triggered by a loss of some sort and I think of it as a malignant sadness that has got completely out of control. The origin of a depressive illness is complex, and vulnerability to depression has a strong genetic component. The amygdala is a key structure in the brain intimately involved in processing emotion; its overactivity - which may initiate, and be sustained by, negative thinking - could cause depression. Treatment can work by breaking this vicious negative cycle, either by reducing the relevant brain activity with a drug like Seroxat, or by controlling the negative thoughts. A combination can be particularly effective, as in my case.

In the United Kingdom, tens of thousands of patients take Seroxat daily. There has not been a single legal claim against its makers over any side effects. Judges in the US, on grounds that I find impenetrable, awarded damages to a family who claimed the drug drove a man to kill his wife. How could one possibly know that this was due to the antidepressant? The only way is by doing carefully controlled trials involving many patients - anecdotal evidence will not do.

There are indeed side effects, and these are listed in the leaflet that comes with the drug, but perhaps not enough emphasis is put on reports of increased agitation and possible suicidal thoughts when the drug is first taken. These antidepressants are not addictive, but one needs to come off them slowly. Patients should be warned about this, and also that there is an increased danger of suicide at the early stages of recovery, when there is the energy to carry out any suicidal intentions. This is the case no matter what treatment causes the depression to go away.

There is no good evidence that any one antidepressant is more effective than another, but they do vary in their side-effects and how an individual will respond. The problem for depressives is to find the antidepressant that works best for them. I will continue to take Seroxat, probably until I die. I cannot face another attack of depression.