Abstract: Objective To explore the regularity and cause of cluster signals of the adverse drug events and analyze the potential risks and problems in the use of drugs, so as to provide reference for the drug safety warning in the work. Methods Cluster signals of 804 cases of adverse drug events were summerized and analyzed from 2014 to 2017 in Anhui province. Results The mainly drugs involved in cluster signals were injections and antitumor drugs, in which more severe signals were reported. Distribution of events was concentrated in the fourth quarter of each year, the main factors were warning rules, number of reports, reporting habits, reporting quality and others. Conclusion The monitoring and handling of cluster signals of the adverse drug events can timely find the possible risk and problems. It also can improve the responsiveness of drug safety incidents, and effectively play the role of risk prevention and control.

Key words: cluster signals of adverse drug events, warning system, analysis