Researchers observed that patients who expected harm were more likely to report side effects, suggesting that nocebos can significantly influence clinical trial outcomes.

When the patient reported new pain after taking the sugar pill, the doctor explained that a nocebo can cause symptoms through negative expectation alone.

Even a simple warning about possible side effects can trigger the nocebo effect, causing patients to report symptoms they would otherwise not experience.

Reports of increased pain following harmless treatments are often attributed to nocebo effects.