Kennedy emphasized that his use of the term nocebo refers strictly to a subject-centered response, a quality "inherent in the patient rather than in the remedy".
[9] In the narrowest sense, a nocebo response occurs when a drug-trial subject's symptoms are worsened by the administration of an inert, sham,[10] or dummy (simulator) treatment, called a placebo.
[13] In 1954, Lasagna, Mosteller, von Felsinger, and Beecher[14] found in a carefully designed study that there was no way that any observer could determine, by testing or by interview, which subjects would manifest placebo reactions and which would not.
Experiments have shown that no relationship exists between an person's measured hypnotic susceptibility and their manifestation of nocebo or placebo responses.
[15][16][17] Based on a biosemiotic model (2022), Goli explains how harm and/or healing expectations lead to a multimodal image and form transient allostatic or homeostatic interoceptive feelings, demonstrating how repetitive experiences of a potential body induce epigenetic changes and form new attractors, such as nocebos and placeboes, in the actual body.
[21] A 2013 review found that nearly 1 out of 20 patients receiving a placebo in clinical trials for depression dropped out due to adverse events, which were believed to have been caused by the nocebo effect.
In the UK, publicity in 2013 about the apparent side effects caused hundreds of thousands of patients to stop taking statins, leading to an estimated 2,000 additional cardiovascular events in the subsequent years.
[30] A third problem is that the prescriber does not know whether the relevant subjects consider the effects they experience desirable or undesirable until some time after the drugs have been administered.
Rubel in 1964 spoke of "culture-bound" syndromes, those "from which members of a particular group claim to suffer and for which their culture provides an etiology, diagnosis, preventive measures, and regimens of healing".
[37] Some researchers have pointed out that the harm caused by communicating with patients about potential treatment adverse events raises an ethical issue.