This case describes a patient with a complex medical history and unstable INR on warfarin. The authors describe the likely cause of the instability and demonstrate the use of oral supplementation with Vitamin K. We have all experienced patients with unstable INR (admittedly not usually as complex as this patient) and that makes this case all the more interesting.

Supplemental vitamin K improves the stability of anticoagulation in a patient with low tissue stores of vitamin K secondary to coeliac disease