A patient is on warfarin therapy for the prevention of deep venous thrombosis (DVT). The respiratory therapist should advise the patient to avoid eating all of the following EXCEPT:

a. broccoli.
b. spinach.
c. liver.
d. grapefruit.
e. orange juice.

E
Patients on warfarin should be advised to avoid foods that are high in vitamin K (which affects blood clotting), such as broccoli, spinach and other leafy green vegetables, liver, grapefruit, and grapefruit juice. Green tea may also need to be avoided. Orange juice is high in potassium, but this is unrelated to warfarin therapy.