Nocebo phenomenon

The term "Nocebo" (latin, "I shall harm") was coined in 1961 by Kennedy to highlight the negative counterpart of the placebo phenomenon so as to be able to distinguish the adverse from the beneficial effects of placebos. It concerns the occurrence of adverse effects because they are expected to develop, attributed to the intervention. Originally, in analogy with placebo, the term was used to describe an inactive substance or ineffective treatment with the aim to elicit negative expectations by verbally suggesting an increase in symptoms. Today, the nocebo effect is an ill effect caused by the suggestion or belief that something is harmful. It's considered a psychobiological phenomenon deriving from a negative psychosocial context surrounding the treatment, resulting in a worsening of symptoms caused by negative expectations and in without the administration of any inert substance. If compared to placebo effect, this phenomenon has only recently received wider attention from basic scientists and clinicians but is still poorly understood. The reason might be found in the stressful and anxiogenic nature of this procedure limiting its ethic al investigation.