Power of Placebo

So, Kaptchuk and his research team set out to see if different kinds of dummy treatments, or placebos could reduce patients' chronic arm pain. They compared a fake acupuncture procedure to a pill made of nothing but cornstarch. They found that, "A dummy procedure has a bigger impact on reducing pain than an oral dummy pill," he says.

As they reported in the British Medical Journal, the study began by testing the effectiveness of two placebo treatments against active treatments at reducing self-assessed arm pain. "You can't give patients placebos without having a comparison with an act of intervention," explains Kaptchuk. After two weeks, the fake pill and fake acupuncture groups were continued and compared against each other.

The volunteers receiving twice-weekly, sham acupuncture treatments reported significantly more pain relief than those taking a fake pill every day. He says it was the more elaborate nature of the acupuncture procedure that gave the volunteers more pain relief.

"Some rituals have bigger effects than other rituals," Kaptchuk says.

The researchers were surprised to find that almost a third of the volunteers claimed to have side effects from their fake treatments. "At the end of the study, 30 percent of the patients, both [in the sham acupuncture and sham pill] arms of the study, reported adverse effects," explains Kaptchuk. "And what was really remarkable is that the adverse effects were completely different depending on, they totally mimicked what we told them in the informed consent." Volunteers who got the sham acupuncture reported feeling pain or irritation from the trick needles, while taking make-believe drug resulted in side effects that included dizziness, restlessness, rashes, headaches, nausea and in four cases nightmares.

"That's suggesting very strongly that how you tell people to pay attention to their experiences, their bodily experiences, helps form, in dramatic ways, what they actually experience," he says. "It was one of the nice, unexpected, but very important findings in the study."

Historically placebos were used to treat patients, but with the development of informed consent in the 1960s that was considered unethical. "Now placebos are only used as controls for an act of intervention in clinical experiments or basic science experiments," he says.

So, while Kaptchuk doesn't suggest doctors give out placebos, he says they should consider not only how to treat a patient, but how they treat a patient.