nocebo effect

1. The reverse of the placebo effect.

2. It's when you expect to hate something and you end up hating it.

1. Kennedy chose the Latin word nocebo ("I shall harm") because it was the opposite of the Latin word placebo ("I shall please"), and used it to denote the counterpart of the placebo response: namely, an "unpleasant" response to the application of real or sham treatment.

2. I hated the food because I expected it to suck. That's nocebo effect for ya.

by swvfan October 2, 2012

Hard Problem of the Nocebo Effect

The ethical and clinical dilemma of how to inform patients of risks without inducing those very risks through the information itself. The principle of informed consent demands full disclosure of potential side effects. But the act of disclosure can dramatically increase the likelihood and severity of those effects via the nocebo pathway. This puts doctors in a Catch-22: withhold information and be unethical, or disclose it and potentially harm the patient through the power of suggestion. Medicine has no good protocol for navigating this.

Example: A doctor must prescribe a statin. The leaflet lists possible side effects: muscle pain, fatigue, cognitive fog. The patient, now anxious and hyper-vigilant, experiences all three. It's impossible to clinically distinguish between a genuine pharmacological side effect and a nocebo-induced one. The hard problem: How do you practice evidence-based, ethical medicine when the communication of evidence becomes a potent confounding variable that can generate its own adverse data? The diagnostic process can become pathogenic. Hard Problem of the Nocebo Effect.

by Dumuabzu January 25, 2026