Abstract

Background Thorough information of the patient is an integral part of the process of shared decision making. We aimed to investigate if detailed information about medication may induce nocebo effects. Methods We conducted a randomized, single-blind, pilot-study including n = 51 psychiatric in-patients aged between 18 and 80 years with a depressive disorder and accompanying sleeping disorders. In the intervention group we provided thorough information about adverse effects, while the control group received only a simple consent procedure. In both groups, patients received an open-label placebo pill instead of their sleeping medication. Results No statistically significant differences between the intervention group and the control group were found regarding the main outcome parameter. Conclusion In this study, we were not able detect an effect of informed consent vs. simple consent on the emergence of placebo or nocebo effects. This finding is contrary to most assumptions and publications about this topic. Trial registration Trial registration number: DRKS00017653, registered August 30th 2018. Retrosprectively registered.