Most people have heard of the placebo effect, in which patients given sugar pills feel better because they think the pills are medicine. But few would like to be on the receiving end of a placebo: A person who asks for a painkiller wants the real thing.
The medical profession, at least officially, frowns upon prescribing placebos, because it usually involves lying, implies disrespect and can destroy trust in doctors. Some hospitals ban placebos, except in experiments, and then participants must be told that they might be given inert pills or shots.
A new survey, though, suggests that the profession may not always practice what it preaches. In the survey of 89 doctors and nurses in Israel, 60 percent said they had given patients placebos. Many said placebos could sometimes work, and more than a third reported prescribing them as often as once a month.
The patients given fake medicine included women in labor and people suffering from pain, anxiety, agitation, vertigo, sleep problems, asthma and drug withdrawal. Most had no idea that they were getting placebos. Among the prescribers, 68 percent told patients they were receiving real medicine, 17 percent said nothing at all, 11 percent said the medicine was "nonspecific" and 4 percent told patients the truth.
Asked why they prescribed placebos, 43 percent said patients had made "unjustified" demands for medicine; 28 percent did it to test whether a patient's symptoms were real or imaginary; 15 percent hoped to buy time before the next dose of real medicine; and 11 percent said their reason was "to get patient to stop complaining."
The doctors who conducted the survey said they had expected that no more than 10 percent of those who responded would have used placebos.
"This is apparently a common practice," said Dr. Pesach Lichtenberg, a psychiatrist at Herzog Hospital and Hadassah medical school in Jerusalem.
He conducted the survey, with Dr. Uriel Nitzan, at two large hospitals and various community clinics in the Jerusalem area. Their report was published online Sept. 17 by BMJ, a British medical journal.
The notion of a placebo effect dates at least as far back as Hippocrates, who observed that certain gravely ill people seemed to recover through sheer "contentment" with their doctors. Thinking the mind could heal the body, later physicians sometimes tried to help it along by giving inert pills or powders to sick people they could not otherwise help.
Today, some researchers are studying the placebo effect, while others doubt that it even exists.
Lichtenberg said he thought the placebo effect was real, could sometimes help patients and could do so more safely than many drugs. "I think the placebo has a legitimate place in medical treatment," he said, but added that it was wrong to lie to patients.
"There are certain ethical questions," he said. "Do you tell a patient, "I'm giving you an antibiotic or a painkiller,' when it's not? Or do you tell them, "You are getting an agent which has been proven effective repeatedly in research, which will help you feel better; we're not exactly sure how it works, but it has been shown to cause changes in brain imaging, to have physiological effects in the body, and we are confident you will get relief'?"
Dr. Robert M. Wachter, chief of the medical service at the medical center at the University of California at San Francisco, said in an e-mail message: "The use of placebos in day-to-day clinical care is virtually unheard of in the United States."
He continued, "They are thought of as a subtle form of deception _ both unethical and potentially creating a small risk of a malpractice suit."
But Wachter also said the placebo effect accounted for much of the benefit people got from antidepressants and all of the benefit from antibiotics taken for viral infections, which are not affected by the drugs.