A study published in Science Translational Medicine shows that expectations can shape both a drug’s benefits and negative side effects. Using functional MRI technology, researchers tracked study participants’ reaction to pain under three conditions: participants had no expectation of receiving pain killers (in this case, a potent opiod); participants expected pain relief from the medication; and participants expected that the medication would actually make the pain worse.
Researchers found that positive expectations made the medication twice as effective. On the other hand, when they had negative expectations the pain killers were essentially useless. Different parts of the brain were stimulated depending on whether the participants were optimistic or pessimistic about the effects of the drug.
The scientists concluded that patients’ expectations are critical to the effectiveness of a prescribed drug. They also say that “may be necessary to integrate patients’ beliefs and expectations into drug treatment regimes alongside traditional considerations in order to optimize treatment outcomes.” Source: https://stm.sciencemag.org/content/3/70/70ra14.abstract