Study: Placebos Really Don't Work

ByAmy Malick

May 24, 2001 -- Does that pill you are taking really work? Or do you feel better just because you think it works?

Physicians have long held that some part of the benefits we get from medical treatment is due to the placebo effect.

A placebo is any kind of pretend medical treatment, such as a sugar pill, which has no known beneficial medical value. The placebo effect is the phenomenon where people's illnesses improve even after receiving this type of treatment. It has also been thought to play a role when people take active medications.

While it may seem doubtful that people can get better taking fake medicine, the placebo effect has been reported countless times in medical literature since the phenomenon was first explained in 1955.

Doctors suspect placebos work by influencing a person's expectation of how well they should feel, which leads to both emotional and physiologically changes that make the person actually feel better.

But a new study in the New England Journal of Medicine challenges the existence of this widely accepted phenomenon. The authors analyzed more than 100 medical studies that compared how people responded to placebos — including sugar pills and false procedures performed — to how people responded to no treatment at all.

Placebos Don't Have Effect Once Thought

We found little evidence that placebos in general have powerful clinical effects … although they had possible small benefits in studies with continuous subjective outcomes [when patients rate how they feel instead of answering yes/no questions] and for the treatment of pain, state authors Asbjorn Hrobjartsson and Peter Gotszche.

The researchers say it will still be important to use placebos in clinical studies so that doctors can accurately measure the effects of new drugs.

The report flies directly against current medical dogma that has recognized the existence of the placebo effect since the middle 19th century. It has long been accepted that placebos have a therapeutic effect," says Dr. Brian Strom, chair of biostatistics and epidemiology at the University of Pennsylvania School of Medicine." This study throws that belief into question.

If the study's findings are correct, then the benefits we feel after taking a pill or receiving a medical treatment are not just "in our heads," but are due to the activity of the treatment.

Strom and others, however, do caution that the study has several limitations. The data available to the authors is just not enough to make any changes in our general beliefs regarding the placebo effect, states David Savitz, chair of epidemiology at the University of North Carolina School of Public Health.

If Placebos Don't Work, Why Do People Feel Better?

The researchers believe that what many doctors call a placebo effect may be simply a natural tendency for a certain percentage of patients to get better on their own over time.

This study is very useful for reminding clinicians that patients can experience spontaneous positive changes which have nothing to do with any type of treatment at all, states Dr. Louis Lasagna, chair of The Tufts Center for the Study of Drug Development and an authority on the placebo effect.

Lasagna also points out that not everyone is equally susceptible to the placebo effect, Patients with a positive orientation to medicine and who are more optimistic will be more likely to benefit from a placebo than patients with less hopeful attitudes.

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