PURPOSE: To describe a potential drug interaction between warfarin and the combination of remdesivir with dexamethasone .
SUMMARY: Two male patients, a 71-year-old and 62-year-old presented to the emergency department for symptoms of coronavirus disease 2019 (COVID-19). Both patients were on long-term warfarin therapy with their most recent international normalized ratio (INR) prior to admission within their patient specific goal as managed by their outpatient Pharmacist . In both instances, the patients denied any changes in diet, lifestyle, or missed doses of medications upon admission interview . During admission, both patients experienced a marked elevation in INR within 24 to 48 hours of the initiation of remdesivir with dexamethasone for COVID-19 pneumonia directed therapy . The patients were both eventually stable and were instructed to continue warfarin monitoring and management under the direction of their outpatient Pharmacist upon discharge .
CONCLUSION: The underrecognized but probable interaction between warfarin in conjunction with remdesivir and dexamethasone warrants further analysis.