March 4, 2008 -- New research shows that people who thought they were given a pricier painkiller reported less pain than those who believe they took the same drug at a discounted price.
Researchers from MIT and Duke University tested 82 healthy volunteers in 2006. None of the participants was told of the study's purpose.
All were told they were going to see how well a new FDA-approved painkiller worked.
The participants were then lightly shocked on their wrists. Half of the group was given what they were told was the new pill, which cost $2.50. The other half was given what they were told was the same new drug, but at a discounted price of $0.10 a pill. No reason was given for the discount.
Both groups were actually given the same placebo pill.
Among the findings:
- 85% of the participants in the regular-price pill group said they had reduced pain on average.
- Only 61% of the group who thought they were getting the cheaper pill said their average pain eased.
Mystery of the Placebo
"The placebo effect is one of the most fascinating, least harnessed forces in the universe," study researcher Dan Ariely, PhD, says in a news release.
Ariely says perhaps prescription medications should come in more appealing packaging, instead of in simple plastic bottles.
"How do we give people cheaper medication, or a generic, without them thinking it won't work?" he says.
Study authors believe the findings may help explain why people more often choose expensive drugs over generic ones.
They recommend that similar research be carried out among a broader population and in hospitals.
The study was funded by MIT. The findings appear in a letter in the March 5 edition of The Journal of the American Medical Association.