gms | German Medical Science

The placebo effect has often been considered a nuisance in basic and particularly clinical research. This view has gradually changed in recent years due to deeper insight into the neuro-bio-behavioral mechanisms steering both the placebo and nocebo responses, the evil twin of placebo. Placebo and nocebo responses are mediated by the quality of the patient-physician communication, the patient expectations towards the benefit of a medical treatment, and associative learning processes. They modulate fundamentally symptom perception, the course of diseases, and the efficacy and tolerability of medical treatment. Converging evidence from experimental and clinical studies has demonstrated that these positive and negative effects on health outcomes are based on complex neurobiological phenomena involving the contribution of distinct CNS as well as peripheral physiologic mechanisms. This knowledge will build the foundation for the exploitation of placebo and nocebo responses for the patient benefit based on mechanism-based and personalized clinical decisions.