Feijoas are a bit of an acquired taste, quite tart, almost medicinal, like an antiseptic ointment. Am I selling them well? People either love or hate them. I love feijoa and ginger loaf, which I’m cooking right now as our daughter-in-law has given us a big bag of fruit from her garden.
Feijoas are in season in NZ at the moment and lots of people have a glut of them which can lead to overindulgence. That’s where the problem starts; There are lots of foods that can interact with warfarin and change the INR result, but so long as you eat roughly the same amount each week it doesn’t usually cause any issues. It’s if you suddenly eat lots of one food (for instance a whole head of broccoli) that contains a lot of Vitamin K, that you can get into problems.
A pharmacist, monitoring warfarin using our INR Online software, emailed us to say a patient’s INR had suddenly become difficult to control and the patient had mentioned eating lots of feijoas. We checked the vitamin K content of feijoas, using the nifty little tool at www.inrtracker.com, and found it is fairly high, similar to that in raspberries and cherries. Other pharmacists have mentioned seeing unusual INR readings from people eating feijoas.
Have any of you experienced this? We’re not sure if it’s just due to the vitamin K content or something magical in this unusual fruit!