Assessment of potential drug-drug interactions in hospitalized cancer patients

Introduction: Drug-drug interactions (DDIs) pose a significant threat to patients with cancer, resulting in several adverse events in an oncology setting. Our study aims to identify potential DDIs in inpatient oncology wards, assess their severity, and provide recommendations to avoid these interactions.

Materials and methods: This prospective study was conducted in 79 hospitalized cancer patients over a period of 9 months (from August 2021 to May 2022) at the Amrita Institute of Medical Sciences, Kochi receiving at least two oncological or non-oncological drugs for 5 days.

Results: Significant differences were found in drug count (61.6% vs. 38.4%), hospitalization duration (63.1% vs. 36.9%), and medications for comorbidities (63% vs. 37%) between patients with and without DDIs (p < 0.001, <0.001, and 0.01, respectively). The study identified 321 DDIs, with 14 (4.4%) X interactions, 93 (30%) D interactions, 161 (50%) C interactions, and 53 (15.6%) B interactions. Severity-wise, 76 (23.7%) were major, 190 (59.1%) were moderate, and 55 (17.2%) were minor.

Conclusion: Our study showed that drug count, medications for comorbidities, and hospitalization duration significantly increase the risk of DDIs in hospitalized oncology patients. Around 96.4% of recommendations for potential interactions were accepted and implemented, highlighting the huge opportunities and requirements for improvement, implementation, and management of drug interactions in oncology settings.