Power of the placebo

Studies are showing that placebos prescribed to unknowing (and knowing) patients actually work

Power of the placebo

Stephan Elleringmann/laif/Redux

Updated In Western medicine, placebos have long been the bridesmaids, never the bride. That’s not surprising: they’re sham pills or simulated medical interventions, seen as handmaidens for use in clinical trials rather than the real thing. Their influence, known as the “placebo effect,” is understood to be a perceived (and not necessarily real or measurable) improvement in a medical condition. Now a spate of studies trumpeting placebos’ efficacy and their prevalence in mainstream medical treatment is dramatically shifting that perception.

In March, 2011, a study by the German Medical Association, or BÄK, revealed half of German doctors prescribe placebos—including vitamin pills and homeopathic remedies—and that they were effective treating minor maladies such as an upset stomach. (A study from Erasmus University in the Netherlands in May, 2011, found placebos effectively treated migraines in 36 per cent of participants.)

“Placebos have a stronger impact and are more complex than we realized,” said Christopher Fuchs, the managing director of the BÄK, when the study was released. “They are hugely important in medicine today.” The following month, a McGill University survey triggered shock ripples with its revelation that 20 per cent of Canadian medical school doctors prescribed placebos to unknowing patients and that more than 35 per cent of psychiatrists prescribed medications in “subtherapeutic” doses, or below the minimal recommended therapeutic level. A glimpse into why that is the case can be found in The Emperor’s New Drugs: Exploding the Antidepressant Myth, a new book by British psychologist Irving Kirsch, who embarked on a 15-year scientific quest that examined all 42 FDA reviews of the six most widely used antidepressant drugs; he discovered placebos to be 82 per cent as effective.

Doctors working in pain and general primary care, as well as psychiatrists, are starting to pay close attention to the placebo effect, says Ted Kaptchuk, an associate professor at Harvard Medical School who has studied placebos for over two decades. “For a lot of common complaints that doctors see on a regular basis—the bread and butter of health care—there aren’t a lot of drugs to help. And those that are available are only marginally better than placebos and come with side effects.”

Placebos have limits, Kaptchuk says. “They don’t shrink tumours or help you with memory.” But they can help in areas he defines as “subjective complaints of self-appraisal” such as nausea and pain. That doctors are prescribing placebos doesn’t surprise him: “Physicians are trained to give drugs—they’re a conveyor belt to the pharmaceutical industry. That may sound facetious, but there’s truth to it. So they give sub-optimal doses to please patients, to make people feel they are being taken care of.” This in itself can be therapeutic, says Kaptchuk. He speaks of healing as an art, as well as a science: “A lot of what we’re doing is the context of healing, the ritual of healing, not the drug itself. And sometimes the context is much more powerful than the drug.”

The German study recommended that placebos be used in minor illness where they seem likely to be successful. BÄK is now calling for internationally recognized guidelines. The topic is a thorny one, raising the ethical dilemma of doctors deceiving their patient. The challenge, says Kaptchuk, is to harness placebos’ power without deception. His research suggests it’s possible: one study found 59 per cent of patients with irritable bowel syndrome given placebos described as “sugar pills” reported symptom relief compared to 38 per cent who received no treatment at all.

“Obviously there is a way of being a compassionate, empathetic physician,” Kaptchuk says. “Sometimes that’s enough—our studies show that.” He recently sat in on a clinic with advanced Parkinson’s patients. The doctor was wonderful, he says, “And when patients left, people who could barely walk were walking differently. They were so happy to have her for just half an hour.”

When Kaptchuk looked at placebos and asthma, his team found that patients who were given a placebo inhaler reported the same amount of symptom relief as those with an albuterol inhaler. Although when researchers examined the maximum air volume that patients could exhale, only the patients who used the medicinal inhaler had improved lung function. “It’s clear that for the patient, the ritual of treatment can be very powerful,” Kaptchuk told the National Institute of Health. “This study suggests that in addition to active therapies for fixing diseases, the idea of receiving care is a critical component of what patients value in health care. In a climate of patient dissatisfaction, this may be an important lesson.”

In 2017, Kaptchuk reported on randomized controlled trials where the patients knew they were receiving open-label placebos (sugar pills) and even in those cases subjects found improvement in their symptoms for the kinds of chronic conditions that are often hard to treat, including IBS and lower back pain. While Kaptchuk is not ready to say doctors should follow his lead yet, he makes a case for looking at placebos in a completely different way.

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