Patient PopulationThe study included consecutive adult patients admitted to a medical inpatient service at the 13 hospitals from January 1, 2015, to December 31, 2021, who fulfilled 2 criteria. First, the patient was prescribed 1 or more doses of parenteral ceftriaxone during their hospital stay. Second, the patient was prescribed a PPI during the period between the first and last dose of ceftriaxone. Patients who were not receiving any PPI during ceftriaxone treatment were excluded. This was a convenient sample size based on the study date cutoff.