The purpose of our research was to analyze the clinical use of oral anticancer treatment of cancer, the incidence and type of frequently of potential drug-drug interactions, and the effectiveness of computer generated warnings in screening drug-drug interactions.
This study is a retrospective cohort study based on the outpatient administrative claims data from the medical center in southern Taiwan from the period between January 2007 and December 2007. Information regarding potential drug interactions for oral anticancer drugs was sourced from “Drug Interaction Facts software, version 4.0”. In the drug utilization, the Anatomical Therapeutic Chemical (ATC) digit coding system, International Classification of Diseases, 9 th version, Clinical Modification (ICD9-CM) codes and SPSS software were used for extracting and analyzing the pharmaceutical claims data.
From a total of 2,482 cancer outpatients, 19,066 prescriptions for oral anticancer drugs were recorded. 937 potential drug interactions were identified at an incidence of 4.9%. The incidence of potential interactions was classified according to significance level 1, 2 and 4. The type of onset time most frequently classified was the delayed type. The most common potential drug interaction in significance level 1 was from methotrexate (MTX), but no significant clinical impact. However, Significant level 2 and level 4 of the drug interactions but more clinical significance, although not part of computer alarm items, but worthy of our attention. The detection rate of drug interaction warning system was found to be 89.7%.
Although some drug interactions of anticancer drugs not as significance level 1 and not including in computer alarm items, but possibly result in decreased the anticancer efficacy and increased drug toxicity, and may threaten patient life. To date the literature for oral anticancer drugs are limited, Our research is hoping to get more attention from pharmacy profession to drug interactions of anticancer drugs and the efficacy of current computer warming system, to enhance patient medication safety.