Frequency and Nature of Medication Errors and Adverse Drug Events in Mental Health Hospitals: a Systematic Review

Introduction Little is known about the frequency and nature of medication errors (MEs) and adverse drug events (ADEs) that occur in mental health hospitals. Objectives This systematic review aims to provide an up-to-date and critical appraisal of the epidemiology and nature of MEs and ADEs in this setting. Method Ten electronic databases were searched, including MEDLINE, Embase, CINAHL, International Pharmaceutical Abstracts, PsycINFO, Scopus, British Nursing Index, ASSIA, Web of Science, and Cochrane Database of Systematic Reviews (1999 to October 2016). Studies that examined the rate of MEs or ADEs in mental health hospitals were included, and quality appraisal of the included studies was conducted. Result In total, 20 studies were identified. The rate of MEs ranged from 10.6 to 17.5 per 1000 patient-days (n = 2) and of ADEs from 10.0 to 42.0 per 1000 patient-days (n = 2) with 13.0–17.3% of ADEs found to be preventable. ADEs were rated as clinically significant (66.0–71.0%), serious (28.0–31.0%), or life threatening (1.4–2.0%). Prescribing errors occurred in 4.5–6.3% of newly written or omitted prescription items (n = 3); dispensing errors occurred in 4.6% of opportunities for error (n = 1) and in 8.8% of patients (n = 1); and medication administration errors occurred in 3.3–48.0% of opportunities for error (n = 5). MEs and ADEs were frequently associated with psychotropics, with atypical antipsychotic drugs commonly involved. Variability in study setting and data collection methods limited direct comparisons between studies. Conclusion Medication errors occur frequently in mental health hospitals and are associated with risk of patient harm. Effective interventions are needed to target these events and improve patient safety.