OBJECTIVE: To mine and analyze the adverse drug reaction signals caused by the immunosuppressive agent tacrolimus according to the U. S. Food and Drug Administration（FDA） Adverse Event Reporting System（FAERS） database

so as to provide references for the application safety of drug use in clinic. METHODS: The method of retrospective analysis method

reporting odds ratio（ROR） method and proportional report ratio（PRR）method

data mining and analysis were conducted on tacrolimus-induced adverse event reports of 41 quarters from the1 st quarter of 2009 to the 1 st quarter of 2019 in the FEARS database. RESULTS: A total of 1 365 adverse drug reaction signals caused by tacrolimus were obtained by using ROR method. The signal strength was ranked in descending order to obtain the top 50 signals

among which there were 14 adverse drug reactions not mentioned in the original drug specification

and 2 new systems were involved according to the World Health Organization Terminology Set. New adverse drug reactions mainly focused on urinary system damage

systemic damage

immune dysfunction

respiratory system damage

metabolic and nutritional disorders

and central and peripheral nervous system damage.CONCLUSIONS: There are many adverse drug reactions with wide range of organs and/or systems involved that are not included in the instructions of tacrolimus. It is recommended to be cautious in clinical administration.