Abstract
BACKGROUND: The vast majority of oncology patients is older than 65 years. Due to comorbidities and age-related multimorbidity, patients often use multiple drugs on a routine basis when cancer is diagnosed. The start of antineoplastic drug therapy poses an additional risk to the patients regarding adverse events caused by drug interactions, resulting in decreased/increased efficacy or increased toxicity. PURPOSE: To minimise the probability and risk of drug-drug interactions in haemato-oncology patients by providing a synoptic table with relevant drug interactions between antineoplastic drugs and drugs frequently used in elderly cancer patients. The synoptic table is meant to facilitate clinicians’ prescribing decisions by offering a quick overview of the most relevant interactions in this specific patient population. MATERIAL AND METHODS: Interaction characteristics of pre-elected drugs were evaluated by a systematic literature search covering the summaries of product characteristics and five drug interaction databases (bccancer. bc. ca, drugs. com, Lexi-Interact, Micromedex, Stockley’s Drug Interactions). For each combination of potentially interacting drugs the varying information retrieved on severity, type of interaction and suggested clinical management was assessed by three hospital pharmacists and the final dataset agreed. Concise and standardised wording for type and management of interactions was defined. A self-developed questionnaire was used to determine the clinicians’ satisfaction with the tool. RESULTS: The synoptic table features 26 antineoplastic drugs in alphabetical order and 36 potentially interacting drugs. Only interactions categorised as clinically highly significant or clinically significant (colour-coded in red and yellow, respectively) are recorded. Interactions emerging as class phenomenon were compiled as a combined dataset. Thirty per cent of 47 listed interactions were classified as clinically highly significant. Hard copies and electronic versions of the table were given to the clinicians. The decision support tool was well received by clinicians and members of the certification body. CONCLUSION: The synoptic table on clinically significant drug interactions in elderly cancer patients has proven an easy-to-use and well accepted decision support tool. Regular updates and education of the users are necessary. No conflict of interest