Frequency, Predictors, and Outcomes of the Potential Drug-Drug Interactions in the ICUs of Teaching Hospitals in Ardabil, Northwest of Iran During 2019-2020

Introduction: Drug-drug interactions (DDIs) can reduce therapeutic efficacy and increase the duration and cost of hospitalization so that patients are sometimes exposed to significant complications and even death. Patients in the intensive care unit (ICU) are at higher risk of DDIs for a variety of reasons, including impaired absorption, decreased metabolism, and renal failure. The main objective of this study was to evaluate frequency, clinical ranking and risk factors of potential DDIs in the ICUs of 3 teaching hospitals in Ardabil. Methods: In this descriptive-analytical cross-sectional study, drug prescriptions 355 patients admitted to the ICUs were studied. Patient information including age, sex, diagnosis, number of prescribers, number of drugs, length of stay, and status of patients' discharge (recovery or death) were recorded and checked using the online software up to date and the book Drug Interaction Facts. Finally, the data were statistically analyzed using the SPSS software. Results: The number of patients studied was 355. The mean age of the patients were 51.88 ± 23.22 years, and on average, 8.45 drugs had been prescribed for each patient. The total number of DDIs was 1597 among which class X was 1.4%, class D was 26.2%, and class C was 67.7%. Four hundred ninety-seven unique pairs of DDIs were identified. Age, number of prescribed drugs and length of stay in ICU were associated with prevalence of DDIs. Age and number of drugs were also identified as the risk factors of patients' discharge caused by death. Conclusion: DDIs can complicate health state of patients in ICUs and may increase the length of hospital stay. Setting up computerized systems to alert drug interactions in hospital wards and pharmacotherapeutic intervention by clinical pharmacist can minimize DDIs.