The quality of online anticancer drug interaction information varies among online drug databases. We describe the creation of OncoRx-IQ, a tool which assesses the information quality of online drug databases for anticancer drug interactions, and a pilot study done with the tool.OncoRx-IQ was designed in the form of a questionnaire containing 25 questions in three quality domains, separated into two sections (Section A: content accuracy and Section B: ease-of-use and reliability). Each question was scored based on the number of options assigned.A pilot study utilizing this tool was done on four drug databases (Drugs.com, Drug Digest, Medscape and Micromedex). Statistical analyses of the composite and domain scores were done using descriptive statistics, Spearman's correlation coefficient and Friedman and Wilcoxon signed-rank tests.Six pre-registration pharmacists participated in the pilot study.The drug databases were evaluated based on the accuracy of their drug interaction content, usability and reliability, as well as their overall quality.Micromedex (66.9%) and Drug Digest (35.8%) were the highest and lowest scoring databases, respectively. Micromedex scored the highest in all quality domains (content accuracy 56.3%, ease-of-use 75.0% and reliability 73.6%), whereas Drug Digest scored the lowest in content accuracy (8.0%) and reliability (48.2%).We have created and pilot-tested OncoRx-IQ, a quality assessment tool, which helps clinicians systematically evaluate the quality and information accuracy of drug databases for anticancer drug interaction information. We hope this tool can lay the groundwork for future long-term evaluation of online drug interaction information.