To tell the truth, the whole truth, may do patients harm: the problem of the nocebo effect for informed consent.

The principle of informed consent obligates physicians to explain possible side effects when prescribing medications. This disclosure may itself induce adverse effects through expectancy mechanisms known as nocebo effects, contradicting the principle of nonmaleficence. Rigorous research suggests that providing patients with a detailed enumeration of every possible adverse event-especially subjective self-appraised symptoms-can actually increase side effects. Describing one version of what might happen (clinical "facts") may actually create outcomes that are different from what would have happened without this information (another version of "facts"). This essay argues that the perceived tension between balancing informed consent with nonmaleficence might be resolved by recognizing that adverse effects have no clear black or white "truth." This essay suggests a pragmatic approach for providers to minimize nocebo responses while still maintaining patient autonomy through "contextualized informed consent," which takes into account possible side effects, the patient being treated, and the particular diagnosis involved.