More Britons than ever are taking antidepressant drugs — prescriptions for the most common type, known as SSRIs (serotonin selective reuptake inhibitors), rose by 165 per cent between 1998 and 2012.

But a controversial new book, The Sedated Society, claims these drugs, said to correct a chemical imbalance in the brain, are the wrong thing to give to emotionally vulnerable people — adults or children.

In an excoriating assessment of the drug industry and psychiatry, experts claim the evidence for antidepressants is flawed and say the drugs have never been shown to correct a chemical imbalance.

Yet millions are being prescribed drugs that are potentially extremely harmful.

Viscount Hinchingbrooke (pictured) was prescribed antidepressant medication he didn't need for about 20 years, and went through hell coming off them

Last week, Good Health published a searing account from one of the book's authors, Viscount Hinchingbrooke, about the 20 years he was prescribed these drugs — medication he didn't need — and the hell of coming off them.

His ordeal is all too common as one of his co-authors, Professor Peter Gøtzsche, a highly regarded expert who specialises in clinical research, design and analysis at the University of Copenhagen, spells out.

'The drugs have failed to deliver what patients want, which is for the treatment to work for specific mental or emotional problems. So, there is no justification for widespread, life-long use.

'People are kept on these drugs for years. Clinicians claim this is to prevent a relapse, but the side-effects of stopping can be so severe it is preferable to stay on them.'

But this is not the only concern raised by the new book.

According to the ten expert authors, drugs such as SSRIs and the heavyweight tranquillisers known as anti-psychotics, not only are no better than a placebo for most people, but some raise the risk of suicide in children and adults.

They also lower libido and could cause a deeply unpleasant muscular condition called tardive dyskinesia.

Furthermore, they claim the drugs are capable of inflicting long-term damage that lasts even when the patient has stopped taking them.

Research on animals has found that antidepressants can shrink the connections between brain cells and that these don't grow back after the drugs are stopped.

Viscount Hinchingbrooke battled benzodiazepine dependence for years after he receiving the prescription following a sinus operation when he was 19

There might just be a case for accepting the risks of these potentially dangerous side-effects if SSRIs were really effective in relieving depression.

The argument is that depression is due to low levels of the feel good chemical serotonin, so SSRIs slow the rate the brain breaks it down so there is more to boost mood.

However, no research has shown a link between serotonin levels in the brain and depression.

'The disease model has been a disaster,' says Professor Gøtzsche.

'I have never seen any convincing evidence showing a psychiatric disease is causing brain damage, but have seen plenty that medication causes brain damage.'

Even so, the theory is often used to warn patients that if they stopped taking the drugs and felt dreadful this was a sign that their disease was coming back.

Another more plausible explanation is that, since SSRIs and other psychiatric drugs are well-known to be addictive, the distressing symptoms are the result of going cold turkey.

The argument is that depression is due to low levels of the feel good chemical serotonin, so SSRIs slow the rate the brain breaks it down so there is more to boost mood

These withdrawal effects can last for years, as Viscount Hinchingbrooke described last week.

Another reason to be suspicious of the theory is the extraordinary lengths the drug companies were prepared to go to get favourable results, such as hiding unfavourable ones or fudging the statistics, as Professor Gøtzsche sets out in the new book.

A basic principle of randomised controlled trials (RCT) — the gold standard for testing any new drug — is that no one involved, doctor or patient, knows which group of patients is getting the drug and which the placebo.

But within two weeks of the main trial for Prozac starting, researchers for the manufacturer had ignored this principle and switched patients between groups, which improved results.

Even worse, to reduce the risk that Prozac raised the risk of suicide (a side-effect that had emerged in earlier trials), 25 per cent of the patients getting Prozac were given a tranquilliser — though this information didn't emerge at the time.

According to the ten expert authors, drugs such as SSRIs and the heavyweight tranquillisers known as anti-psychotics, not only are no better than a placebo for most people

When U.S. drugs watchdog the FDA (Food and Drug Administration) discovered what had been done — according to another of the book's authors, Dr Peter Breggin, a psychiatrist who has written books on Prozac — it calculated the benefit of Prozac without the tranquilliser was no better than a placebo.

On the basis of such flawed evidence, Prozac launched in 1987. Other brands followed, and one — Seroxat — ran trials to get a licence to treat childhood depression, but it emerged they were misleading.

In 2002, the BBC's Panorama revealed that some of these trials had found Seroxat increased the risk of suicide in children, but the manufacturer had put these embarrassing results in a bottom drawer and never published them.

The Panorama programme was the first time the curtain concealing what goes on behind the scenes in drug trials had been pulled back.

A UK committee on drugs announced Prozac was the only SSRI that could be safely used by children, despite the known suicide risk for adults.

However, there were no penalties for the company concealing the suicide risk.

A UK committee on drugs announced Prozac was the only SSRI that could be safely used by children. However, there were no penalties for the company concealing the suicide risk

Prozac had been handed a great marketing opportunity, but the Panorama revelations had dented people's trust in SSRIs, so a new series of trials called TADS (Treatment of Adolescents with Depression Study) began in the U.S. at the American National Institutes of Mental Health.

It compared Prozac plus CBT (cognitive behavioural therapy) with Prozac alone, or a placebo, and claimed results showed Prozac in combination with CBT to be safe and effective for children.

But as with so many SSRI trials, favourable results were obtained by a simple but effective sleight of hand, says another of the book's authors, Professor Sami Timimi, a consultant child and adolescent psychiatrist and Director of Medical Education in the National Health Service in Lincolnshire.

Only positive results were reported in the summary of the trial — you had to dig through the whole article to find the truth, says Professor Timimi.

'The headline conclusion from the first TADS study was that Prozac plus CBT [cognitive behaviour therapy] was the best option for children,' he writes.

'In the full text, well hidden, was much worse news for Prozac. When compared directly with a placebo, it was no better.'

Millions of patients are currently being prescribed drugs that are potentially seriously harmful

Also hidden was the suicide risk, he says. None of the children getting a placebo or therapy had any risk while a clear link with Prozac showed up.

In a fierce broadside on the profession, Professor Gøtzsche believes the large sums of money brought into psychiatry from the drug companies, because of the theory that depression was due to low levels of serotonin, was a key factor in allowing this data to stand unquestioned.

At the same time that TADS was apparently giving Prozac a clean bill of health, psychologist Professor Irving Kirsch, associate director of the Harvard Program in Placebo Studies, published the results of his analysis of unpublished SSRI trials, held by the FDA.

These were largely ignored. So, for many people the drugs don't work, says the new book.

But drugs that don't work and could actually harm a patient are also clearly deeply worrying.

In addition to the raised risk of suicide and the serious problems that some patients have with withdrawal, there is the risk, though rare, of a deeply unpleasant side-effect from long-term use of anti-depressants known as tardive dyskinesia (TD), the result of permanent brain changes.

In addition to the raised risk of suicide and the serious problems that some patients have with withdrawal, there is the risk of permanent brain changes

Sufferers lose control of muscles, especially around the head and neck and in the arms and legs.

Trying to come off SSRIs can produce a similar condition known as akathisia, which Dr Breggin describes as 'an extreme form of restlessness, where patients can't sit still and that predisposes to suicide and homicide'.

So what should be done to ensure that children and adults seeking help for depression get it in a safe and effective way?

Peter Kinderman, professor of clinical psychology at the University of Liverpool, another of the book's authors, believes that the solution is to return to an approach that treats people's emotional needs directly, rather than with drugs on the basis of an unproven theory about brain chemistry.

This winding the clock back has far-reaching implications.

'Mental health should no longer be controlled by psychiatrists,' says Professor Kinderman, who is president of the British Psychological Society.

'They are the profession that prescribes drugs for mental disorders and improvements would come from cutting back prescribing to almost zero.'

The Sedated Society edited by James Davies (Palgrave Macmillan, £25).