Surprising number of doctors prescribe placebos

Jan 6 2008

The revelation that doctors in the U.S. commonly prescribe placebos has surprised many.

A study by researchers at the University of Chicago has found that almost half of the doctors surveyed had prescribed a dummy pill at some point.

The researchers suggest the study results raise ethical questions and they say there is a need for greater recognition and understanding of the use of placebos.

The theory with placebos is that if patients think they are getting an effective treatment, they sometimes feel better, even though the pill has no proven benefit.

They are often used in clinical trials to compare the benefits of drugs, and many times patients taking placebos show some improvement however few studies have shown how doctors use placebos in routine practice.

The study authors medical student Rachel Sherman and Dr. John Hickner, a family medicine professor at the University, sent surveys to 466 internists at three Chicago-area academic medical centers and they received 231 responses.

Of those 231, 45 percent said they had used a placebo during their clinical practice, which surprised the researchers; another 12 percent of those surveyed said placebos should never be used.

Sherman suggests that some physicians believe the body's natural healing potential may be underestimated, but the use of placebos raises ethical issues, including whether a doctor has an obligation to provide patients with informed consent.

Of the doctors who reported prescribing a placebo, 34 percent said they told the patients the substance was something that "may help and will not hurt," a third gave other information to patients including, "this may help you but I am not sure how it works," 19 percent said it was a "medication," and 9 percent called it "a medicine with no specific effect;" only 4 percent of the doctors said, "it is a placebo."

Sherman says one of the reasons doctors are not forthcoming about giving a placebo is that in order for it to work, patients need to believe it can help.

The authors say 96 percent of doctors in the study believed placebos can have therapeutic benefits for patients.

Sherman says placebos have been used in medicine since ancient times, and remain both clinically relevant and philosophically interesting.

As well as their recognized use as controls in clinical trials, this study suggests says Sherman that placebos themselves are viewed as therapeutic tools in medical practice.

Sherman says if all new patients are asked for their consent in advance, the ethical dilemmas are then avoided.

The doctors most commonly defined a placebo as an intervention not expected to have an effect through a known or specific physiologic mechanism and the majority of doctors believed in both psychological and physiological benefits.

The study is published in the January issue of Journal of General Internal Medicine.