March 4, 2008— -- The more expensive your pain medications are, the better the relief you get from taking them — even if they're fake.
That's according to a study published this week in the Journal of the American Medical Association, which suggests that sugar pills labeled as expensive drugs relieve pain better than sugar pills labeled as discounted drugs.
Researchers often compare real drugs to sugar pills in medical studies to account for the placebo effect, in which the illusion of taking medicine alone can cause symptoms to disappear.
But Dan Ariely, a behavioral economist at Duke University in Durham, N.C., and a team of collaborators from the Massachusetts Institute of Technology compared the placebo effect of the marketing that people are asked to swallow along with their medicine.
In the study, 82 volunteers were subjected to a series of electric shocks — a standard research protocol for measuring pain thresholds. They were then given a placebo pill alongside a fake drug company brochure for the fictitious drug "Veladone-Rx," — ostensibly a new fast-acting painkiller made in China.
The only catch was that half of the test subjects received brochures showing that the drug had been marked down from the original price of $2.50 a pill to 10 cents a pill. These modified brochures also included circled fine print which suggested that the pills were manufactured in China.
After participants went through the shocks again, 85 percent in the full-price group reported pain relief from their sugar pill, while only 61 percent in the discount group reported pain relief.
"In a way, placebo is a big part of medicine," said Ariely, who wrote an entire book on the subject called "Predictably Irrational."
The placebo effect goes beyond simple perception. In fact, people taking placebos for pain relief will secrete higher levels of the body's natural painkillers called endogenous opioids, said Ariely.
"But the interesting thing is, we can't close our eyes and say, 'please can I get some pain relief?'" said Ariely. "It's under our control, but not under our control consciously."