A placebo can work even when you know it’s a placebo

Mallika Marshall, MD

Contributing Editor

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If your doctor told you that she was giving you a placebo and that it would help you, would you believe her? As it turns out, based on new research, maybe you should.

Placebos are often considered “fake” treatments. You may have heard them described as “sugar pills.” They usually take the form of pills, injections, or even entire procedures that are used in clinical trials to test “real” treatments. For example, one group of study participants is given an active drug and another group is given a placebo, which looks exactly like the active medication but is completely inactive. The participants can’t tell whether they’re getting the fake drug or the real drug. The researchers wait to see if the people taking the real one do better (or worse) than those taking the fake one.

To complicate matters, there is a documented “placebo effect,” which means that some people actually respond to a placebo even though it shouldn’t have an effect on the body. This has been thought to be largely due to their beliefs or expectations that they are getting the real treatment and not the fake one. But what if people were told, up-front, that they were getting a placebo and not an active medication? It stands to reason the placebo would have no effect. Right?


What an “open-label placebo” can do for you

Dr. Ted J. Kaptchuk, a professor of medicine at Harvard Medical School and director of the Harvard-wide Program in Placebo Studies and the Therapeutic Encounter (PiPS) at Beth Israel Deaconess Medical Center in Boston, has been studying placebos for more than 20 years. His most recent work on these “open-label placebos,” as they’re called, is fascinating. I had a chance to interview him in person earlier this year.

In one study, Kaptchuk looked at people with irritable bowel syndrome (IBS), a common condition that causes abdominal cramping and diarrhea or constipation that can be debilitating for many. Half of the study volunteers were told they were getting an “open-label” placebo and the others got nothing at all. He found that there was a dramatic and significant improvement in the placebo group’s IBS symptoms, even though they were explicitly told they were getting a “sugar pill” without any active medication.

Kaptchuk says placebos won’t work for every medical situation—for example, they can’t lower cholesterol or cure cancer. But they can work for conditions that are defined by “self-observation” symptoms like pain, nausea, or fatigue.

“People can still get a placebo response, even though they know they are on a placebo,” he adds. “You don’t need deception or concealment for many conditions to get a significant and meaningful placebo effect.”

Are open-label placebos a promising new strategy?

Kaptchuk says more research is needed — and some is currently under way. He has another study at the Dana-Farber Cancer Institute studying cancer-related fatigue. And a recent study overseas looking at open-label placebo for chronic low back pain looks promising. If placebo works for chronic pain, explains Kaptchuk, it could allow patients to reduce their doses of opioid medications and help prevent addiction.

“Our hope is that in conditions where the open-label placebo might be valuable, instead of putting people on drugs immediately — for depression, chronic pain, fatigue — that people would be put on placebo,” says Kaptchuk. “If it works, great. If not, then go on to drugs.”

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