18th August 2020

A 77-year-old man attends a GP appointment, with some questions about a new medication he has been prescribed

A 77-year-old man attends a GP appointment, with some questions about a new medication he has been prescribed. He recently had a heart valve replacement and has been started on warfarin following this. He says he was given a lot of information about the drug, including being told not to eat a lot of leafy green vegetables, which he thought was quite bizarre.   

Which of the following statements about the mechanism of warfarin explains the advice that was given to this patient?

Select the SINGLE most appropriate option from the list below. Select ONE option only.