Abstract

The primary and secondary objectives of this study were to identify and assess the risks associated with the occurrence of drug-drug interactions (DDIs) and to determine the value of pharmacists' interventions in the management of clinically significant DDIs, respectively.
A prospective, case-control study was carried out on patients admitted to the intensive care unit (ICU), and involved a review of patients' medication chart daily by the pharmacist and the clinical parameters. All identified DDIs were carefully analysed in order to provide recommendations on the management of clinically significant DDIs.
The majority of DDIs were categorised as Type-C severity level (n = 305, 75.9%). 'Substitution' was recommended in 34 cases of clinically significant DDIs, 'dosage adjustment' in 17 (4.2%) and 'stop or avoid' in 13 (3.2%). The number of drugs prescribed (p = 0.001, rS = 0.539) and length of ICU stay (p = 0.001, rS = 0.364) were significantly associated and positively correlated with the occurrence of DDIs. Patients with DDIs had a longer length of ICU stay than those without DDIs (9.5 days vs. 2.4 days, p = 0.001). No significant difference was found between patients aged below 50 years and those above 50 years (odds ratio 0.488, 95% confidence interval 0.166-1.434) in terms of the risk of DDIs.
A large number of DDIs were identified in this study, but only a small number were clinically significant. Pharmacists' participation in daily ward rounds could play an important role in the detection and management of clinically significant DDIs.