Study measures healing power of expectations

Outliers was intrigued by a new study that suggests physicians should be as careful in describing a drug's effects to patients as when they prescribe it.

Boston researchers recruited 66 migraine patients in an attempt to quantify how much of their pain relief came from a medication and how much was due to the placebo effect. More than 450 headaches later, they reported last week that it's important for doctors to carefully choose what they tell patients about a powerful medicine—because the message could help enhance its benefits, or blunt them.

“Every word you say counts, not only every gram of the medication,” said Harvard University professor Ted Kaptchuk, who led the study with a team at Boston's Beth Israel Deaconess Medical Center.

Here's how it worked. Patients who suffer regular migraines agreed to forgo pain relievers for several hours during one attack, recording their symptoms for comparison with later headaches.

Then for each of their next six migraines, the patients were given a different pill inside an envelope with a different message. Sometimes they were told it was an effective migraine drug named rizatriptan, a positive message. Other times they were told it was a placebo, a dummy pill, suggesting no benefit. Still other times they were told the pill could be either one, a neutral message. Sometimes they were told they got rizatriptan and they really did. Sometimes researchers switched the pills.

While the real migraine drug worked far better than the dummy pill, people who knew they were taking a placebo still reported less pain than when they had left their migraine untreated.

The surprise: Patients' reports of pain relief more than doubled when they were told the migraine drug was real than when they were told, falsely, that it was a fake, the team reported in the journal Science Translational Medicine.

“The more we gave a positive message to the patient, the bigger the placebo effect was,” Kaptchuk said.

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