Posts tagged nocebo

Posts tagged nocebo
Researchers have identified a novel mechanism that helps explain the power of placebos and nocebos.
Described in the Sept. 10 on-line issue of the Proceedings of the National Academy of Sciences (PNAS), the new findings demonstrate that the placebo effect can be activated outside of conscious awareness, and provide an explanation for how patients can show clinical improvement even when they receive treatments devoid of active ingredients or of known therapeutic efficacy.
"In this study, we used a novel experimental design and found that placebo and nocebo [negative placebo] effects rely on brain mechanisms that are not dependent on cognitive awareness," explains first author Karin Jensen, PhD, of the Department of Psychiatry and the Martinos Center for Biomedical Imaging at Massachusetts General Hospital (MGH) and the Program in Placebo Studies (PiPS) at Beth Israel Deaconess Medical Center/Harvard Medical School. "A person can have a placebo or nocebo response even if he or she is unaware of any suggestion of improvement or anticipation of getting worse."
ScienceDaily (July 12, 2012) — Negative suggestion can induce symptoms of illness. Nocebo effects are the adverse events that occur during sham treatment and/or as a result of negative expectations. While the positive counterpart — the placebo effect — has been intensively studied in recent years, the scientific literature contains few studies on nocebo phenomena. In the latest issue of Deutsches Ärzteblatt International, Winfried Häuser of the Technical University of Munich and his co-authors present the underlying neurobiological mechanisms and highlight the relevance of the nocebo effect in everyday clinical practice.
Nocebo responses can, for instance, be brought about by unintended negative suggestion on the part of doctors or nurses, e.g., when informing the patient about the possible complications of a proposed treatment. It is also assumed that a certain proportion of the undesired effects of drugs can be attributed to nocebo effects. The mechanisms behind this phenomenon are — as with placebo effects — learning by Pavlovian conditioning and reaction to induced expectations.
What are the consequences for clinical practice? Doctors find themselves in an ethical dilemma between their obligation to tell the patient about the possible side effects of a treatment and their duty to minimize the risk of a medical intervention and thus to avoid triggering nocebo effects. As one possible strategy to solve this dilemma, Häuser et al. suggest emphasizing the tolerability of therapeutic measures. Another option, with the patient’s permission, would be to desist from discussing undesired effects during the patient briefing.
Source: Science Daily