This is the fourteenth installment of our look at the increasingly high placebo response that is plaguing clinical trials in analgesia and psychiatry. Read the rest of the posts in the series here.
The term “placebo” first took hold in an unlikely place: funerals. Placebo, Latin for “I shall please” first came into use in the 14th century, and was the name for a professional mourner, an individual who was paid to stand in for a family member of the deceased and “sing placebos,” a term for the chanting of the phrase “Placebo Domino in regione vivorum” (which translates to “I will please the Lord in the land of the living”).
Thus, the term placebo came to mean something that was pleasing and satisfying. Over time, placebo singers began to have a derogatory connotation, likely due to their low social status, and the term placebo also came to be synonymous with a sycophant, like Geoffrey Chaucer’s character Placebo in Canterbury Tales.
The first placebo-controlled medical experiment was conducted in 1784 by Benjamin Franklin and Antoine Lavoisier, who used placebos to discount Franz Mesmer’s theory of mesmerism, which claimed that an invisible natural force called “animal magnetism” could produce strange bodily sensations that culminated in healing. Franklin and Lavoisier’s experiment involved the exposure of participants to both regular objects such as trees they were told had been “magnetized” (the term for objects that had been treated by Mesmer to elicit healing powers), as well as trees that had been authentically but secretly “magnetized.” Participants experienced effects in the former case but not the latter, leading the team to conclude that the effects were due to imagination.
According to a historical overview of placebo use in medicine, placebo was first defined in a medical dictionary the following year as “a commonplace method or medicine.” By 1811, was defined as “an epithet given to any medicine adapted more to please than to benefit the patient.”
However, it was Henry Beecher who first popularized the concept of the placebo effect and demonstrated its importance in modern medicine. In a now-famous 1955 JAMA article entitled “The Powerful Placebo,” Beecher presented the results of 15 placebo-controlled trials and reported that the average placebo improvement was substantial—about 35 percent. In hindsight, the vast majority of these studies did not include a no treatment group, making it impossible to say whether the observed effects were due to the placebo effect itself or the natural course of disease (see our eleventh post in this series for more information on disease-related contributors to the placebo response). Nevertheless, it was Beecher’s seminal paper that cemented the placebo response as a legitimate medical phenomenon.
Join us next week for our final post of our Placebo Problem series, where we’ll take a look at some of the ethical issues surrounding the use of placebos. You can rewind to the beginning of the series here.