A student-and-professor team at the University of Chicago surveyed 466 faculty physicians at Chicago-area medical schools. Almost half of the 231 respondents — 45% — said they had prescribed placebos in regular clinical practice. Among the reasons the doctors gave: to calm a patient down, to respond to demands for medication that the doctor felt was unnecessary, or simply to do something after all other clinical treatment options had failed. Most prescribing doctors felt they were doing the right thing. Of all the physicians surveyed — whether or not they had prescribed placebos — 96% believed that dummy pills could have real therapeutic effects. If placebos work by manipulating a patient's expectations, then prescribing them suggests that doctors are deliberately deceiving their patients.

Doctors seem aware of this quandary. Twelve percent of survey participants said they thought placebos should be banned completely from regular clinical practice. Among the doctors who prescribed them, one in five said they outright lied to patients by claiming a placebo was medication. The American Medical Association (AMA), the largest association of U.S. doctors and medical students, tells its members that "[p]hysicians may use placebos for diagnosis or treatment only if the patient is informed of and agrees to its use."

But wouldn't disclosure drain the power from a placebo? Not necessarily, according to the AMA. Once physicians have been given general permission to use placebos, the AMA's guidelines say, they don't need identify to their patients which treatments are true medical interventions and which are not: "In this way the physician respects the patient's autonomy and fosters a trusting relationship, while the patient still may benefit from the placebo effect."

AMA also reveals a fundamental change in the way modern scientists view the relationship between mind and body. In 1979, a similar survey of American doctors found that 60% of respondents believed that using placebos was a good way to deduce whether a patient had a "real" problem or was just faking it. In the current study, 80% of doctors disagreed with that statement. "That's a significant shift in doctors' thinking in a relatively short time," - says lead author Rachel Sherman, a fourth-year medical student at the University of Chicago. Today, few doctors balk when patients say they have pain but show nothing abnormal in scans. "Physicians in this survey believe the mind and the body are inherently interconnected, and that belief can challenge our approach to the healing process in new, innovative ways," - she says.