Genetics
Genes also have an influence on how patients react to placebo treatments. As a matter of fact, lots of people are genetically predisposed to react to placebos. One study even discovered that people with a gene variant that codes for higher levels of the brain chemical dopamine are expected to react differently to the placebo effect compared to those with a low-dopamine version.
Even more, people with the high-dopamine version of the same gene tend to have higher levels of pain perception and reward seeking.
The Nocebo effect
Contrarily, some individuals might experience more side effects as a response to the placebo, or as a response that’s sometimes known as the “nocebo effect.” For instance, a patient might suffer from headaches, nausea, or even dizziness after taking the placebo medication.
