The study aimed to investigate the prevalence of drug-related emergency department (ED) visits and associated risk factors. This retrospective cohort study was conducted in the ED, Diakonhjemmet Hospital, Oslo, Norway. From April 2017 to May 2018, 402 patients allocated to the intervention group in a randomized controlled trial were included in this sub-study. During their ED visit, these patients received medication reconciliation and medication review conducted by study pharmacists, in addition to standard care. Retrospectively, an interdisciplinary team assessed the reconciled drug list and identified drug-related issues alongside demographics, final diagnosis, and laboratory tests for all patients to determine whether their ED visit was drug-related. The study population’s median age was 67 years (IQR 27, range 19–96), and patients used a median of 4 regular drugs (IQR 6, range 0–19). In total, 79 (19.7%) patients had a drug-related ED visits, and identified risk factors were increasing age, increasing number of regular drugs and medical referral reason. Adverse effects (72.2%) and non-adherence (16.5%) were the most common causes of drug-related ED visits. Antithrombotic agents were most frequently involved in drug-related ED visits, while immunosuppressants had the highest relative frequency. Only 11.4% of the identified drug-related ED visits were documented by physicians during ED/hospital stay. In the investigated population, 19.7% had a drug-related ED visit, indicating that drug-related ED visits are a major concern. If not recognized and handled, this could be a threat against patient safety. Identified risk factors can be used to identify patients in need of additional attention regarding their drug list during the ED visit.

This innovative prioritizing model is designed to be practical in the fast-paced workflow at the ED and can identify what patients are at increased risk of having crMDs. The multidisciplinary working model was proven time efficient and could contribute towards increased patient safety.