In my early twenties I was felled by a bout of mental illness. It started with a panic attack. I was standing on the station at Leamington Spa waiting for a train and shivering slightly in the early autumnal chill when, without warning, a paralysing wave of fear broke over me. The terror that swept over me that afternoon was intense. Although an otherwise unremarkable day – I was waiting for the London train to visit my girlfriend – I might as well have been in line for my own annihilation, so strong and so plausible was the fear.

In the coming weeks and months my mind began to come apart. It was by some degree the most unpleasant experience of my life. I went from being an extrovert, if confused, young man, fascinated by life, in love with its colours and textures, to being a dragging, empty shell, spooked by my own shadow, panicked by my own thoughts. To take one among numberless examples: it is a strange and unsettling thing to awake one morning from uneasy dreams to find yourself frightened of the colour white.

After hauling myself for many months through a grey kaleidoscope of miseries – I could never have anticipated the physical pain that mental illness brings: the pounding head, the burning skin, the deep muscular ache – I found myself face to face with a psychiatrist in a featureless room in a hospital in North London. It is a curious thing, visiting a psychiatrist for the first time. A few years earlier I had been seriously ill with a psoas abscess, outcome of a late appendectomy. And yet for all my time in hospital I never once felt as I did visiting that psychiatrist. Physical illness is something that happens to you. Mental illness is you. It is one thing to say that your body is sick, quite another to say it of your mind.

I spent some time recounting my woes to my silent and watchful psychiatrist. I spoke of my terrors, of sleepless nights, of thoughts that squeaked and gibbered in my head. She listened, she nodded, she made some mutterings. And then she said her piece. ‘There is’, she said, ‘a flaw in your personality. You will have to fix it.’ So was this then the sum of psychiatric expertise? What knowledge I wonder did she think she added to the world that day? What good did she think she had done? I too was more than capable of stating the blindingly obvious.

Although by nature a fellow-traveller, my experience of depression – for this is what my woe was finally called – has left me with a long unease when it comes to anti or critical psychiatry. Take a recent posting on this site by Stephen Ginn, which owes something to this movement. “In truth,” he writes, “‘depression’ is a very difficult thing to define and any doctor who says that they can reliably differentiate it from sadness is deluding themselves.” Many things in life are difficult to define – illness itself is a good example – but it does not follow that they do not exist. As Ginn also points out, one of the ways we try and grasp things is to distinguish them from things that they are not. This too can be difficult, particularly at the thresholds. But although it is not easy to say at dusk the point at which light becomes dark, day is not the same as night.

The baddy in Ginn’s picture is the over-prescribing of anti-depressants. It is, he implies, the outcome of a folie-a-deux between doctor and patient. Medicalising unhappiness and prescribing pills is easier than admitting to the complex genesis of mental misery and to the limits of medical efficacy. There must be some truth in this. But then he goes further: ‘I’m not going to go so far as to say that there is no such things as “mood disorder” but in recent years we have all re-imagined humans as intensely vulnerable beings, which inevitably means that people will view themselves in this light.’ And then I start to part company. After my psychiatrist’s signal disappointment I returned to my GP. She could tell I was in trouble. She prescribed me anti-depressants. When things were really tough she saw me once a week. Slowly, painfully slowly, I wound my way out. The anti-depressants did not ‘cure’ me, but they lifted me from the depths. Without them I could not have made the changes in my life that needed to be made. She had no complex theories about the world, at least none that she shared with me. When people were ill she tried what lay at hand to help. Quietly and compassionately she steered me towards recovery.

Although anti-psychiatry dresses itself in liberal clothes, seeking to rid the world of stigma, it courts a greater tyranny. Depression is not the same as ordinary unhappiness. It is a state unlike any other I have experienced. Ideas about being vulnerable neither made me ill nor ameliorated my distress: in truth like many twenty-year olds, before it hit me I had thought myself invulnerable. Defining suffering away does not diminish it. It insults it. Be wary what you mean when you say to patients, as Ginn does: you do not need anti-depressants, you’re a lot tougher than you think. It could be the cruellest form of paternalism yet.

Julian Sheather is ethics manager at the British Medical Association. The views expressed are his own.