THE PLACEBO EFFECT

When patients visit a doctor, they usually leave with a prescription for a medicine. However, some long-term conditions – such as persistent back pain – often require powerful drugs with serious side effects. “We don’t like to keep people on these drugs for long periods,” says Dr. Jeffrey Wilkins, a pain specialist. “So some of us prescribe a ‘placebo,’ namely fake pills that only contain sugar or flour. We tell the patients that the pills might help. And, in fact, many appear to get as much relief from the placebo as from conventional drugs – without the risk of side effects.”

Research has shown that placebos can provide some relief from a wide range of medical conditions, including long-term pain and difficulty sleeping. This might explain why a surprisingly
large number of doctors prescribe placebos. An international survey of pain specialists, for instance,found that over 50% do so regularly. According to the survey, those prescribing a placebo assume it will only work if patients believe it is a genuine medicine. Therefore, they don’t tell them the truth.
“This is a serious ethical problem,” says medical journalist Carolyn Nicholson. “Even if the doctor has good intentions, is lying to a patient ever acceptable?”

Professor Ted Kaptchuk of the Harvard Medical School, a world expert on what is called “the placebo effect,” has made some intriguing discoveries. In a recent experiment, for example, he gave placebo pills to a large group of patients who had suffered from pain for many years. However, he made it clear to them that the only ingredient in their pills was sugar. To his amazement, many of them reported significant improvement. Kaptchuk has also been trying to identify the underlying mechanisms that might explain why placebos are helpful. So in another of his experiments, patients with long-term pain were given placebos and then had brain scans. The scans showed that their brains subsequently started producing dopamine and endorphins – chemicals that block pain.

“These findings suggest that the success of placebos has a lot to do with a patient’s expectations,” says Nicholson. “Most of us have so much faith in doctors that if one of them gives us a pill,
we’ll probably believe it’ll help us no matter what it contains. And this belief may somehow trigger the production of helpful chemicals in the brain.” Moreover, Nicholson thinks the expectation of a good outcome might also explain why some alternative treatments have helped so many people. “That’s the most likely reason,” she says. “After all, scientists haven’t found any active ingredients in the substances they tested.”

Whereas most researchers focus on the effect of placebos on medical conditions, others are now revealing their impact on very different aspects of our lives. It has been found, for example, that athletes ran farther after taking placebo pills that were described as “performance-enhancing” by the doctors prescribing them. So although there is still much to learn about placebos, one thing is clear – their effect can be extremely powerful.