Absolute contraindications of warfarin: Previous CNS bleeding Recent neurosurgery Active frank bleeding Early pregnancy and delivery Relative contraindications: Active peptic ulcer disease Chronic alcoholism Bleeding diathesis Severe hypeension Severity and type of liver disease may influence warfarin pharmacokinetics. Severe cholestatic liver disease reduces CYP2C content, while severe cirrhotic liver without cholestasis does not. Ref: Inpatient Anticoagulation By Margaret C. Fang, 2011, Page 34; Primary Care Medicine Recommendations By Allan H. Goroll, Albe G. Mulley, Jr., 2001, Page 224; Goodman and Gillman's 11th edition, Page 955-956.