Evaluation of potential drug-drug interactions in intensive care unit

Abstract

Objective: Potential drug-drug interactions (pDDIs) and adverse drug reactions (ADRs) may be frequently observed in critically ill patients because of multiple drug use. It is important to identify pDDIs before their progression to ADRs. This study aimed to determine the prevalence and effect of pDDIs and possible ADRs in intensive care patients.

Patients and methods: In this retrospective cross-sectional study, the medical records of patients in the intensive care unit (ICU) of Bursa Uludag University Faculty of Medicine Hospital between January 1, 2018, and December 31, 2018, were examined. Medication orders were recorded on days 2, 5, and 10. pDDIs, defined using the lexi-interact (UpToDate, 2020), were classified based on the significance level.

Results: A total of 144 patients were included in this study, and from the 395 medication orders, 1,776 had pDDIs. Of these interactions, 23.5% were major (n = 418), 71.4% were moderate (n = 1268), and 5.1% (n = 90) were minor. The majority of patients (96.9%) had at least one pDDI. There was a strong correlation between the number of drugs on days 2, 5, and 10 and the number of pDDIs (p < 0.001, ρ = 0.7; p < 0.001, ρ = 0.72; p < 0.001, ρ = 0.73, respectively). No significant correlation was found among the number of pDDIs, the APACHE II score, and the duration of ICU stay.

Conclusions: The prevalence of pDDIs was high and there was a strong correlation between the number of drugs and pDDIs. Detection of potential interactions through clinical decision support systems and checker tools should be used to increase patient safety.