Placebo response: relevance to the rheumatic diseases.

Recent interest in the neurobiology of the placebo effect has brought about a new awareness of its potential exploitation for patient benefit, framing it as a positive context effect with the power to influence therapy outcome. Among the different placebo effects described in clinical conditions and experimental settings, placebo analgesia is of particular relevance to the rheumatologist. Placebo analgesia is the field that has most contributed to our understanding of the multiple mechanisms underlying this phenomenon. The possible clinical applications of placebo studies range from the design of clinical trials incorporating specific recommendations and minimizing the use of placebo arms to the optimization of the context surrounding the patient so that the placebo component in any treatment is maximized.