Abstract: Objective To investigate the incidence and causes of medication errors (ME) related to cefoperazone / sulbactam in the elderly (≥ 60 years old) so as to provide data for targeted precautions. Methods Reports about cefoperazone / sulbactam-related ME in the elderly were retrieved from the National Monitoring Network for Clinical Safe Drug Medication between September 22, 2012 and September 22, 2021. The severity of errors, content of errors, locations of errors, the person(s) responsible, and causes of errors were retrospectively analyzed. Results A total of 210 ME reports were retrieved, involving 143 males and 67 females, with a median age of 73 (60 to 97). In terms of severity of errors, errors of Class B (Minor ME) were dominating (139 cases, 66.19%). There were 10 cases of severe ME ( 4.76%): 4 patients with severe liver insufficiency were prescribed with cefoperazone / sulbactam, which aggravated their liver function, 2 patients at a high risk of bleeding had not had their blood coagulation indexes monitored, resulting in prolonged prothrombintime (PT), and one of them even suffered upper gastrointestinal tract bleeding, 2 patients with bleeding events did not discontinue medication immediately, which prolonged their PT, 1 patient presented with renal insufficiency after using cefoperazone / sulbactam, but did not stop medication immediately, resulting in severe renal insufficiency, and 1 patient with anaphylactic shock did not choose to use epinephrine first. Among these 213 ME, 140 (24.29%) were made by physicians. The top three types of errors were related to the dosage, frequency ( qd ) and variety. Most of these ME were due to a lack of knowledge or training and fatigue. ME made by pharmacists (51 cases, 24.29%) were mainly related to the variety (LASA drugs). One hundred and fifty-two (72.38%) of these errors were spotted by pharmacists. Conclusion The proportion of severe ME concerning cefoperazone/ sulbactam is higher than that of severe ME related to clinical drugs across the country. Errors associated with prescriptions and dispensing merit attention. Importance should be attached to the selection of the right drug variety, quick dose adjustment, monitoring of coagulation disorders and to prevention of combined use of drugs containing ethanol excipients in patients with hepatorenal insufficiency. It is recommended that information be made more accessible to reduce the ME related to prescriptions, drug selection be taken seriously, labels of LASA drugs be made more eye-catching to lower the risk of LASA errors. Clinicians ought to be better informed of rational drug use, and rescue processes for anaphylactic shock have to be formulated.

Key words: cefoperazone/sulbactam, elderly, medication safety, medication errors