Medication-safety burden of omeprazole in psychiatric inpatients: A retrospective cross-sectional study

ObjectiveOmeprazole is commonly prescribed to psychiatric inpatients with polypharmacy; however, empiric initiation, prolonged treatment, intravenous use, and screening-flagged potential drug-drug interactions or co-administration patterns may complicate medication review. This study described omeprazole prescribing patterns, appropriateness, and utilization intensity in a psychiatric specialty hospital.MethodsThis retrospective cross-sectional study used routinely collected data from hospital information systems and electronic health records of a municipal psychiatric specialty hospital in Shanghai, China. Consecutive inpatient omeprazole orders issued between 1 February 2023 and 31 December 2024 were screened. After excluding invalid, duplicate, and incomplete records, 152 eligible prescriptions of 71 inpatients were analyzed. Outcomes included guideline concordance for indication, dose, duration or review plan, route of administration, drug-drug interaction-based utilization, IV use, and screening-flagged potential drug-drug interactions or co-administration patterns. Analyses were primarily descriptive.ResultsAppropriate indication was documented in 57/152 prescriptions (37.5%), dose appropriateness in 147/152 (96.7%), and guideline-concordant duration or review plan in 36/152 (23.7%). Overall, 31/152 prescriptions (20.4%) were fully appropriate, 22/152 (14.5%) needed to be optimized, and 99/152 (65.1%) were inappropriate; thus, 121/152 prescriptions (79.6%) were not fully appropriate. Screening-flagged potential drug-drug interactions or co-administration patterns were present in 77/152 prescriptions (50.7%). Weighted exposure was 1.86 drug-drug interactions per treatment day. Intravenous therapy accounted for 13.1% of treatment days and 21.6% of total drug-drug interactions, with a median intravenous course duration of 7 days.ConclusionsOmeprazole prescribing frequently showed non-concordance with predefined appropriateness criteria, mainly involving indication documentation or selection, treatment duration, and route optimization. Screening-flagged potential drug-drug interactions and drug-drug interaction/day should be interpreted as medication-review and utilization signals rather than as confirmed adverse events or direct evidence of inappropriate prescribing.