Disproportionality analysis of drug-induced dry mouth using data from the United States food and drug administration adverse event reporting system database

Background: Drug-induced dry mouth is an adverse reaction that can significantly affect the quality of life and mental state of patients. In this study, we aimed to identify the most common drugs associated with dry mouth using data from the United States Food and Drug Administration Adverse Event Reporting System (FAERS) database. Methods: We accessed data from the FAERS database between the first quarter of 2004 and the first quarter of 2024. The Medical Dictionary for Regulatory Activities was used to identify reports of dry mouth, and disproportionality analyses (reporting odds ratio, proportional reporting ratio, Bayesian confidence propagation neural network, and multi-item gamma Poisson shrinker) were performed to examine the risk signals for dry mouth and its causative drugs. Results: A total of 75,899 adverse event reports were related to dry mouth. Tiotropium bromide monohydrate (2080 cases) was associated with the majority of dry mouth cases. Disproportionality analysis revealed that the top five drugs with the highest reporting odds ratio (ROR) were darifenacin, solifenacin succinate, fesoterodine fumarate, tolterodine tartrate, and niraparib. Moreover, eight of the top 19 drugs that caused dry mouth were not identified as having major side effects in the package inserts. Conclusion: Tiotropium bromide monohydrate was the most frequently reported drug for dry mouth, whereas darifenacin had the highest ROR. Collectively, our findings emphasize the necessity for improved recognition and management of drug-induced dry mouth, particularly for medications not adequately flagged for this side effect in their labels.