LAUSR

Background: Drug interactions are common drug-related problems that can lead to adverse drug reactions and hospitalization. Aims: The objectives of the study were to determine the potential drug–drug interactions (pDDIs) in Northern Cyprus community pharmacies and to compare three electronic databases regarding the frequency, mechanism, and severity of drug–drug interactions. Material and Methods: A retrospective observational study was conducted between July 1 and September 30, 2021, in Northern Cyprus community pharmacies using the Drugs.com, Lexicomp, and Medscape databases. The Mann–Whitney U-test was used to determine the difference between the values of the databases. Pearson's correlation was used to determine the association between DDIs and polypharmacy. Results: A total of 558 (52.1%) of 1072 prescriptions were included in the study. Drugs.com, Lexicomp, and Medscape databases detected 185, 176, and 213 potential drug–drug interactions in patients' prescriptions, respectively. There was a statistically significant difference in moderate drug interactions between the Medscape and Lexicomp databases (p = 0.02). Pearson's correlation showed a weak association (Medscape: r = 0.296, Lexicomp: r = 0.341, Drugs.com: r = 0.289, P = 0.0001) between pDDIs and polypharmacy. The assessment of agreement on severity of pDDIs characterized by Drugs.com and Lexicomp databases using the Kappa index was moderate agreement (0.509, P = 0.0001), while Drugs.com and Medscape databases using the Kappa index were moderate agreement (0.442, P = 0.0001), and Lexicomp and Medscape databases using the Kappa index were fair agreement (0.365, P = 0.0001). Conclusions: This study showed that Medscape detected more potential DDIs than Drugs.com and Lexicomp. Therefore, we propose that more than one database should be used to evaluate and identify pDDIs in pharmacy.