Abstract: Objective To explore the clinical characteristics of and risk factors for severe thrombocytopenia caused by cefoperazone sulbactam sodium so as to provide a reference for safe and rational use of drugs. Methods The clinical data of two patients who developed thrombocytopenia after taking cefoperazone sulbactam sodium was analyzed while the mechanism, association and risk factors for thrombocytopenia caused by this drug were explored based on related literature. Results Correlation analysis showed that severe thrombocytopenia was associated with cefoperazone sulbactam sodium in these two patients. The drug was discontinued and the two patients had their symptoms improved after blood transfusion until they were discharged after clinical observation. Conclusion Despite the low incidence of severe thrombocytopenia induced by cefoperazone sulbactam sodium, the consequent adverse reactions can be severe. Clinicians should be alert to the risk factors to ensure early identification and interventions to improve the prognosis of patients.

Key words: Cefoperazone Sulbactam Sodium, Severe Thrombocytopenia, Coagulation Disorder, Drug-Induced Thrombocytopenia, Adverse Drug Reaction