The term placebo is a Latin word meaning “I shall be acceptable or pleasing’”, and describes a phenomenon in which an inert treatment/substance like sugar can improve a patient’s condition, because the patient believes it will help. Conversely, a negative placebo effect is called a nocebo (Latin for “I shall harm”), and is an inert substance or form of therapy that creates harmful effects in a patient.
The Placebo effect is a variable to be controlled for in clinical trials. The first study with a placebo controlled trial took place in 1784 under the request of King Louis XVI. At the time, Benjamin Franklin was the American Ambassador to France and he oversaw the study. Franz Anton Mesmer was claiming a new treatment called animal magnetism. One of his followers was Marie Antoinette but the King was suspicious and wanted the claims to be reviewed. Through the study, the placebo group responded, and Mesemer was called a fraud.
One explanation for the placebo effect is a so called regression to the mean. Over time, most patients will show improvement with or without any treatment. A person usually enrolls in a study when they are feeling their worst so their condition will usually improve solely based on the natural progression of the illness. A study in 1978 led by Jon Levine, Newton Gordon, and Howard Fields used Naloxone to block endorphins. In the study they used patients who had their wisdom teeth extracted and gave them placebos for their pain. Most experienced a reduction in pain. Some of those patients received another placebo while others were given the Naloxone. Those that received Naloxone were in more pain, and they concluded that the placebo effect on pain lies in the brains production of endorphins. This was the first study to show that endorphins and the body chemistry were behind the placebo effect. The neuroscientific explanation of the placebo effect continues to be studied to date. In 2015 Kathyrn Hall and her colleagues suggested that genes also matter in the placebo effect. They looked for links between the strength of the placebo effect and single nucleotide polymorphisms(SNPs). Therefore, people may be genetically predisposed to, or resistant to, the placebo effect. Which could be impactful in patient studies for clinical trials.
Kathyrn Hall is part of PiPs, or the Program in Placebo Studies and Therapeutic Encounter at Harvard Medical School and Beth Israel Deaconess Medical Center. PiPS has recently redefined the Placebo Effect as “the key to understanding the healing that arises from medical ritual, the context of treatment, the patient- provider relationship and the power of imagination, trust, and hope”. PiPS is the first research center to pursue placebo studies, in an effort to try to understand and utilize the effect. Ted Kaptchuk director at PiPS, once said “I realized long ago that at least some people respond even to the suggestion of treatment. We know that. We have for centuries. But unless we figured out how that process worked and unless we did it with data that other researchers would consider valid, nobody would pay attention to a word we said.”
Could placebos prove to be a valuable medical treatment? It is interesting to think that the placebo effect could one day be better understood and harnessed to help treat people.
Written by Michelle Mader, PhD
January 21st, 2016