The liver is the primary organ involved in the metabolism of warfarin, so that the presence of liver disease can profoundly affect the anticoagulant response to warfarin.
Thyrotoxicosis also enhances the response to warfarin and smaller doses are needed.
Patient Education Thorough education of the patient regarding the risks and benefits of anticoagulant therapy is imperative if adherence to the regimen is to be achieved. The patient should also understand the effects that diet, smoking, physical activity, and interacting medication may have on the anticoagulation effect. Patients should be instructed to call if any of these signs or symptoms occur. Warfarin is not like any other drug - it's a very powerful medicine, with great potential for good and, if misused, harmful. As patients often forget verbal instructions, written patient education materials should be provided.