The placebo effect is used regularly in clinical research. It could be used as a treatment for a symptom, in particular to relieve pain. Explanations.
I’placebo effect has been known for a long time. In medicine, a placebo designates a substance without its own pharmacological action but which can relieve symptoms. It has a real effect on the body, psychological but also neurophysiological. ” The mechanism by which the brain secretes endorphins with a placebo has been known for a very long time. This release of neurotransmitters is linked to a waiting for relief effect. These are contextual elements that contribute to creating these expectations: placebo administered by a person wearing a white coat, a stethoscope… informs Pr Nicolas Pinsault, Physiotherapist, head of the Themas team (UMR CNRS/UGA 5525). In clinical trials, the placebo is administered without the patients knowing whether they are taking the placebo or the drug: this is called non-disclosure of the placebo when it is administered without the knowledge of the person taking it. This helps to see if a drug has a greater effect than the placebo.
Why could the placebo be a treatment for the symptom?
The classic placebo has proven its effect on many occasions for the treatment of many symptoms such as pain, anxiety, migraines, Parkinson’s disease, irritable bowel syndrome. (1) Its use is however limited by ethical questions raised by “non-disclosure”. If the patient is informed that he is taking a placebo, we speak of “open” placebo. This removes the ethical problem. ” The open placebo could be used to relieve symptoms. Pain is a good target, it is the most studied phenomenon when we are interested in the placebo. Furthermore, it is a multifactorial and complex symptom with a strong psychosocial component. Finally, some pain can be difficult to relieve and analgesics have side effects explains Professor Nicolas Pinsault. This is why research is being carried out on the value of “open” placebo treatments as a complement to other treatments to reduce pain.
An “open” placebo to relieve pain
For a long time it was thought that the “open” placebo had less effect than the placebo associated with non-disclosure. Some studies have shown that an open placebo has reduced stress before exams or reduced sleep problems. The Placethic study, supported by the Apicil Foundation and conducted by physiotherapists Léo Druart and SaraEve Graham Longsworth and Pr Nicolas Pinsault, researchers within the THEMAS laboratory TIMC/University of Grenoble Alpes-CNRS team, has shown thatan open placebo improved pain the same as a hidden placebo, from the moment the person receives clear information. “Informing the person about the mechanisms of pain and the placebo creates an expectation effect. The neurophysiological phenomenon is then set up to reduce the pain as with a hidden placebosays Leo Druart. The Placethic study was carried out on young volunteers in whom pain was induced (by cold). “We are going to carry out further studies on patients who suffer from chronic pain in order to know if we obtain the same results, and studies comparing the effects of known analgesics and those of open-label placebos.announces Professor Nicolas Pinsault. The results, if they prove conclusive, could make it possible to relieve pain without the side effects analgesic drugs and also to allow patients the choice of pain treatment.
- Can an open-label placebo be as effective as a deceptive placebo? Methodological considerations of a study protocol,Medicines (Basel)Jan 2020
- (1) The placebo response: how words and rituals change the patient’s brain,Patient Educ Couns.Sept 2011
- (2) Placethic study