The Placebo Effect: Cough and Other Conditions It Improves
(LONDON) -- It may not take much to tame a nagging cough. Merely believing that a certain treatment will suppress a cough may do the trick, according to new Australian research.
The Daily Mail reported that people in a very small Australian study who received a placebo instead of a drug had less of an urge to cough after inhaling capsaicin, an ingredient found in chili peppers, than people who received no treatment at all.
Researchers told participants that they were going to inhale either lidocaine, a common anesthetic, to minimize the urge to cough, or a gas, which they were told would not work. In actuality, however, all study participants received the ineffective gas.
The finding that people who thought they received the lidocaine had 45 percent less of an urge to cough than those who knew they were receiving an ineffective treatment surprised researchers, who have long known about the so-called placebo effect, but didn't expect it to be that strong.
"It's difficult to know why that is that cough responds so well to placebo," lead author Stuart Mazzone told the newspaper. Placebos are more effective for coughing than for other conditions, including pain, he said.
"As a physician, the more the placebo effect works, the better," said Dr. Mark Stacy, vice dean for clinical research at Duke University Medical Center. "The more benefit a patient would have, the better."
Placebos seem to bring about a complex response in the brain, said Dr. Charles Raison, an associate professor of psychiatry at the University of Arizona College of Medicine.
"It's probably a combination of therapeutic reliance, hope and expectation, and when the brain perceives them, it is able to change activity in circuits relevant to the condition," he said.
Despite the positive effects research has uncovered, it is unethical for doctors to prescribe placebos without informing patients they're doing it.
And the placebo effect doesn't just work on coughs, experts say. Studies suggest that placebos also bring about positive effects in the conditions on the next few pages.
Copyright 2012 ABC News Radio