Pickles and warfarin interaction: a case-based review

A 36-year-old woman with a history of lupus and antiphospholipid syndrome controlled by warfarin presented to the hospital with left periorbital ecchymosis. She was found to have an INR of 9 despite maintaining her normal warfarin dose of 12.5 mg/15 mg alternating qd. The only identifiable precipitating factor was that the patient recently stopped eating dill pickles. Limiting dietary vitamin K while on warfarin therapy was once considered best practice. However, studies have demonstrated that maintaining a consistent intake of vitamin K is more important than the quantity. Still, many patients on warfarin remain unaware of which foods contain large amounts of vitamin K and are, therefore, susceptible to bleeding sequelae. Practitioners should be educated to inform patients to consume a steady amount of vitamin K in their diet, identify which foods contain vitamin K, and include pickles on that list.