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A look at a medical practice some experts say violates your trust

Placebos include MRI scans and X-ray tests used to assure patients nothing is wrong.

Jochen Sand/Thinkstock

A new study shows that many British doctors routinely prescribe placebos, reflecting a trend seen in other countries, including Canada.

The doctors obviously think they are helping their patients with the power of suggestion. Indeed, studies have shown some patients report an improvement in their symptoms if they believe they have received a treatment – a positive outcome known as the placebo effect. But medical authorities tend to frown on the practice, considering it a form of deception and a violation of the patient's trust.

"Placebos are widely used," said Jeremy Howick at the University of Oxford and a co-leader of the U.K. study. "It's time to take our heads out of the sand and look at ways in which they can benefit patients and maximize the potential gains in an ethical way."

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The main goal of the U.K. study was to get a general idea of how frequently British physicians prescribe placebos. The researchers used a broad definition that included both "pure" and "impure" placebos. Pure placebos are treatments such a sugar pills or saline injections that contain no active ingredients. (This is the type of placebo often used for comparison purposes in clinical trials of new and experimental drugs.)

Impure placebos include sub-clinical doses of a medication or prescribing a drug for a condition it is not designed to treat – such as using bacteria-killing antibiotics for a viral infection like the common cold. They also encompass non-essential physical examinations, X-rays, MRI scans and blood tests performed to reassure patients that nothing is wrong.

For the study, the researchers at Oxford and the University of Southampton e-mailed questionnaires to a random sample of doctors and 783 responded. The findings, published in the online journal PLOS ONE, revealed that 97 per cent of the respondents have prescribed impure placebo treatments, while 12 per cent have used pure placebos.

The survey also found that doctors use pure and impure placebos for essentially the same reasons. They are given either to induce psychological treatment effects, because patients requested treatment or to reassure patients, said Howick.

A similar type of study was conducted in Canada a few years ago – and it found that physicians in this country also use placebos on a regular basis. Of the 600 Canadian doctors who answered the questionnaire, 20 per cent reported using placebos or pseudo-placebos (like sub-clinical doses of a drug), according to the results published in 2011 in the Canadian Journal of Psychiatry.

Placebos have been shown to be "extremely potent" in many fields of medicine, including psychiatry, rheumatology, immunology, pediatrics and even some surgeries, said the lead author of the Canadian study, Dr. Amir Raz, a professor of psychiatry at McGill University in Montreal.

Still, there is a right and a wrong way to use placebos and most doctors don't get proper training in them because the practice is taboo. It's often considered to be unprofessional to use them and some medical authorities think they only produce "fleeting imaginary effects," Raz said in an e-mail.

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"Placebos ... can no longer be ignored in modern medicine," he added. "Placebos are not nothings. They are pretty strong somethings. How strong they are depends on many factors."

While they are strong proponents of placebos, both Raz and Howick agree they must be employed in an ethical way. That means doctors need to be up front with patients, acknowledging they are using placebos.

"Doctors can't deceive the patient – that would be unethical," said Howick.

But how can a placebo be effective if patients are informed the treatment contains no active ingredient? It has long been assumed that patients needed to believe they were getting the real thing in order to benefit from the placebo effect.

Several recent studies – including one by Harvard Medical School researcher Ted Kaptchuk – suggest "even if you tell the patient it is a placebo, it can still work," noted Howick.

"And, of course, they don't just say it is a placebo – it's terrible. They give a positive suggestion that accompanies the placebo pill. And the reasoning it might work is because of classical conditioning," explained Howick. In other words, the effectiveness of a placebo really boils down to the power of positive spin.

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However, even when doctors are acting with the best of intentions, they can still do harm if placebos are not used appropriately.

"Prescribing antibiotics if you are relatively certain it is a viral infection is harmful. And unnecessary MRI scans and X-rays carry financial cost and health risks," explained Howick. "We might want to think of better strategies that are less harmful – maybe a different kind of consultation with the patient" that still takes advantage of the placebo effect.

Howick and his research colleagues in Britain plan to expand their research, exploring how placebos could be put to the best use in the health-care system.

And Raz is continuing his work in Canada. "We have amassed some compelling data in support of placebos in medicine. But change requires more than data. It takes time and advocacy and a proper climate."

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