Drug Interactions and Adverse Events in a Cohort of Warfarin Users Attending Public Health Clinics

Abstract Background: Warfarin is an oral anticoagulant involved in important interactions with foods and other drugs. Objectives: To evaluate the occurrence of adverse events reported by warfarin users and their relationship with drug interactions. Methods: This was an open cohort, prospective study conducted in an 18-month period with warfarin users attending public health clinics of the city of Ijuí, Brazil. Data were collected by means of interviews administered at patients’ home every month. Patients’ responses were confirmed by review of medical records when patients sought medica...