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The mysterious phenomenon known as the nocebo effect describes negative expectancies. This is in contrast to positive expectancies that trigger placebo effects (1). In evolutionary terms, nocebo and placebo effects coexist to favor perceptual mechanisms that anticipate threat and dangerous events (nocebo effects) and promote appetitive and safety behaviors (placebo effects). In randomized placebo-controlled clinical trials, patients that receive placebos often report side effects (nocebos) that are similar to those experienced by patients that receive the investigational treatment (2). Information provided during the informed consent process and divulgence of adverse effects contribute to nocebo effects in clinical trials (1). Nocebo (and placebo) effects engage a complex set of neural circuits in the central nervous system that modulate the perception of touch, pressure, pain, and temperature (1, 3, 4). Commercial features of drugs such as price and labeling influence placebos (5, 6). On page 105 of this issue, Tinnermannet al.(7) show that price also influences nocebo effects.