Complain to your doctor about a mental health problem and you will probably leave the surgery with a prescription for drugs, despite increasing doubts about their effectiveness and fears about side-effects. The prevailing wisdom is that psychiatric disorders are genetically based brain diseases, biological abnormalities that can be controlled with medication. Every year, doctors in England dole out 31 million prescriptions for antidepressants alone.

It is a state of affairs that makes Richard Bentall furious. In 2004, Bentall, professor of clinical psychology at the University of Bangor, wrote Madness Explained, in which he argued that hearing voices, hallucinations and other symptoms of “severe” mental illness are just exaggerations of quirks experienced by us all. That won him the British Psychological Book Of The Year award. Now, in Doctoring The Mind: Why Psychiatric Treatments Fail, he criticises mental health services, and psychiatry in particular.

Doctoring the Mind paints a stark picture of a mental health system riddled with corruption and incompetence, in which shrinks live it up on pharmaceutical company cash while patients are disrespected, dehumanised and drugged to the eyeballs. Like the legendary “anti-psychiatrist” R.D. Laing before him, Bentall believes that people with mental health problems need understanding, support and respect. Unlike Laing, he offers evidence to back his claims, declaring himself a “rational anti-psychiatrist”.

“I am committed to the scientific world-view,” the 53-year-old says, his urgent voice rising above the rush-hour clatter of the station café in which we meet. “But the evidence doesn’t support the hardline biomedical view behind most psychiatric practice.” He takes a sip of coffee, then continues. “More alarmingly, the treatments based on it are not very effective. Outcomes for psychiatric disorders are no better than in the Victorian period.”

So what is the answer? In Bentall’s view, we need nothing less than a wholesale culture-change in our approach to mental illness. He says that psychiatric diagnoses are less reliable than star signs (“at least with star signs you can agree on who has which sign. Psychiatric diagnoses are unreliable and largely invalid”) and that patients are more likely to recover in countries where there are virtually no services: “If you’re going to go mad, do it in Nigeria because you have a better chance there than in London. I’ve had numerous PhD students doing research with patients who have been told ‘you’re the first person to take me seriously’. That’s a shocking indictment of the way the psychiatric system works. In Nigeria, people with severe mental illness tend to be looked after in an extended family system or by supportive religious leaders who tell them not to worry about hearing voices.”

Therein lies the key. According to Bentall, the evidence supports a treatment model that relies on supportive relationships rather than pills. “What works is being kind and listening to people, encouraging them to be optimistic and treating them with respect. The tragedy of psychiatry is that it makes patients feel that they are objects to be chemically tinkered with by a bunch of arrogant people in suits.”

For anxiety and depression, he says, and perhaps for more complex complaints, psychotherapy is at least as effective as medication. “But,” he laments, “the words you will almost never hear from a psychiatrist are ‘the drugs didn’t work, let’s try something else’. What you’ll hear is ‘the drugs didn’t work as well as we’d like, let’s try another drug or more of the same drug’.”

This potentially condemns patients to a lifetime on medication of questionable effectiveness and with strong side-effects. Anti-psychotics, says Bentall, may lead not only to lethargy and weight gain but to diabetes, cardiovascular disease and early death (“these are drugs that don’t get sold on street corners. They are very unpleasant to take”). Perhaps it is understandable, then, that most people with “problems”, even supposedly severe ones, prefer to keep their symptoms to themselves.

“The biomedical model has led to a disrespect of the patient,” Bentall continues. “I have sat in rooms where a psychiatrist has told a patient ‘you’ll be ill for the rest of your life’. That creates hopelessness — and it’s also not true. Psychotherapy encourages them to be optimistic, to feel that they are being cared for and listened to. But psychiatrists don’t usually do psychotherapy — they may see someone for 15 minutes once every three months. Yet there is good evidence that the therapeutic alliance is very powerful, so the first thing to establish in any psychiatric intervention is a good-quality relationship.”

Bentall may be rational but his rage is palpable. He will deliver a broadside at the barest prompting, sometimes for ten minutes or more, with barely a pause for breath.

He stresses that he doesn’t think that “everyone with a medical qualification has horns” — he has many psychiatrist friends and accepts that they work under severe constraints. But, he says, psychiatry has long suffered from a crisis of identity, to which it responds by trying to present itself as a “proper” branch of medicine, or, as he puts it, “establishing credibility in the eyes of anaesthetists and neurosurgeons when perhaps they should have been thinking more about what their patients thought of them”. He dreams of a system in which psychiatrists “celebrate the fact that they are not like other doctors”.

That goal may be a long way off. “Psychiatrists are often less concerned about relationships than other medical specialties. When I was working at a medical school in Liverpool, gynaecologists were always asking us to run workshops on how to relate more effectively to patients. We never had a request like that from psychiatry.” He believes that the only hope is a genuine revolution: “If mental health professionals could be sacked for not establishing good relationships with patients, there would be a big sea-change. Some psychiatrists are not good at it and, frankly, should be advised to seek alternative careers.”

I wonder about Bentall’s career. Why would someone devote his working life to a system that he finds so frustrating? He says that his interest in the mind was sparked at public school, where he passed a “fairly unhappy” youth. “I spent quite a lot of my adolescence depressed,” he says. “At one point I was prescribed antidepressants.” After receiving his first degree and a PhD from Bangor, he did clinical training in Liverpool, took an MA in healthcare philosophy and had a spell as an NHS forensic psychologist before returning to Liverpool and eventually securing professorships there, in Manchester and now back in Bangor.

He has a clinical practice but his first love is research. “I find it immensely exciting when data about some apparently incomprehensible psychological process comes in,” he says. “I sit at my computer, trying to make sense of it.” He smiles. “I think I may have a slightly autistic side.”

The humour fades when we discuss the many studies carried out by pharmaceutical companies, most of which he considers “completely worthless or very close to it”. He cites the case of antidepressants such as Prozac, which were thought until recently to be highly effective. “They seem to work because drug companies publish studies where the antidepressant wins and don’t publish studies where the antidepressant doesn’t win,” he says. “But if you add unpublished trials to the mix you’ll find no such thing.”

I mention a recent analysis that did just that, using the Freedom of Information Act to obtain missing data. It indicated that SSRI antidepressants barely work better than a dummy pill. Bentall nods in agreement. “But prescriptions have tripled in the past decade,” he says, “because drug companies spend so much on marketing.”

He is even more indignant about psychiatrists who accept all-expenses-paid trips to drug company conferences, agree to put their names to pharmaceutical research that they did not conduct and take huge consultancy fees for advice and support — all of which makes the prescription of that company’s products more likely. “There is no other word for it but bribery. Why haven’t psychiatrists stood up to this? They sign up to the Hippocratic oath and tell us that they have the highest ethical standards. They should be outraged; instead they are largely colluding.”

When it comes to the promotion of anti-psychotic drugs for children, supposedly to control difficult behaviour, Bentall finally boils over. “I know what these drugs do and it’s outrageous,” he storms. “There’s no way in a million years that any child I had anything to do with, under any circumstances, would come close to an anti-psychotic. There’s no clinical basis for it, and from what we know of the pharmacology they are clearly bad things to be putting into developing brains. Drug companies are bribing American child psychiatrists with huge research grants to advocate this kind of treatment, and it’s beginning to happen in the UK. I don’t know how else to put it but that people are being bribed to poison children — and accepting the bribe.”

Doctoring the Mind is pessimistic about the prospect of change. Bentall says that psychiatry and drug companies “have a vested interest in keeping things are they are”. But he remains inspired by the times when services work well. After a divorce as a young man, he was referred for therapy with a psychiatrist.“I was terrified,” he admits, “but I was given excellent treatment. Sadly, that’s not the norm.”

Doctoring the Mind: Why Psychiatric Treatments Fail by Richard P. Bentall is published by Allen Lane on June 25 at £25. To order it for £22.50 inc p&p, call 0845 2712134 or visit timesonline.co.uk/booksfirst

Mental health facts

Every year, one British adult in four experiences a mental disorder every year. Only a quarter of those people receive treatment for it.

A person with a severe mental health problem is four times more likely than average to have no close friends.

By 2020, depression is predicted to become the second highest cause of premature death, second only to heart disease.

About 30 per cent of GP consultations are for a mental health problem. Mental health problems costs the UK an estimated £98 billion a year in economic and social costs.

In 2004, £854 million was spent on drug prescriptions for mental health.