Placebos Work Even When You Know

Patients told they were getting a placebo still reported improvements at a much higher rate than patients who were not treated. Karen Hopkin reports

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They say medicine is as much an art as a science. But sometimes it seems more like a mystery. Take, for example, a new study that shows that sugar pills work, even when patients know they’re taking them. The findings appear in the Public Library of Science journal PLoS ONE. [Ted J. Kaptchuk et al., "Placebos without deception: A randomized controlled trial in irritable bowel syndrome"]

The placebo effect’s been well-documented. Patients who receive dummy pills often show clinical improvement. But in all studies to date, the patients believed they were receiving a real drug. Placebos work, doctors believed, because the mind is a powerful thing. Just thinking you’re being treated can make you feel better.

In this study, however, docs told patients they were getting placebos. Eighty patients with irritable bowel syndrome were instructed to take two sugar pills daily. The bottle even had "placebo" printed on it. After three weeks, 60 percent of the placebo group reported relief from symptoms, compared to 35 percent who’d received no treatment at all.

The doctors say it’s possible that the very act of ministering to patients may have a positive effect. Their findings will have to be repeated with more patients and other disorders. In the meantime, a sugar pill that can treat what ails ya is pretty sweet.

—Karen Hopkin

[The above text is a transcript of this podcast.]

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