OBJECTIVE: To probe into the adverse drug reactions of drug-induced thrombocytopenia based on clinical data of patients with drug-induced thrombocytopenia in Jiangsu Shengze Hospital Affiliated to Nanjing Medical University（ hereinafter referred to as“our hospital”）

so as to improve the understanding of clinicians on drug-induced thrombocytopenia and reflect the value of pharmacists. METHODS: Through the LIS system of laboratory department of our hospital

the test data of all patients with platelet counts lower than normal values were collected from 2017 to2020. Patients’ gender

age

platelet count

clinical diagnosis and medication data were investigated through the HIS system and electronic medical records

the causes of the disease were investigated

adverse drug reactions were determined

and the drug types and mechanisms of thrombocytopenia were analyzed. RESULTS: Totally 44 581 cases of test data were collected and 2 024 patients with thrombocytopenia were extracted from LIS system

of which280 patients（ 13. 83%） were drug-induced thrombocytopenia. Among 280 patients with drug-induced thrombocytopenia

135 were males（ 48. 21%） and 145 were females（ 51. 79%）

the majority were aged from 60 to70 years. The drugs that induced thrombocytopenia were mainly antineoplastic drugs（ 234 cases

83. 57%）

including376 case-times of various types of antineoplastic drugs

and the top 3 drugs ranked by the number of case-times were platinum drugs（ 128 case-times

34. 04%）

antimetabolites（ 81 case-times

21. 54%） and anti-tumor botanical drugs（ 67 case-times

17. 82%）. CONCLUSIONS: There are many causes of thrombocytopenia

and according to the investigation

drug-induced thrombocytopenia accounts for the 3 rd highest number of cases. A higher proportion of patients who develop drug-induced thrombocytopenia are the elderly > 60 years old receiving anti-tumor drugs. It is suggested that clinicians need to monitor the use of relevant drugs in high-risk groups and adjust the dose or change the drugs in time to reduce the occurrence of drug-induced thrombocytopenia.