Absolute contraindications to warfarin include: large esophageal varices within 72 hours of major surgery a platelet count less than 50 x 109/cu.mm which constitutes significant thrombocytopenia hypersensitivity to the drug, such as skin ischemic necrosis or priapism clinically significant bleeding condition – reassess risks after three months pregnancy and within 48 hours of delivery because of its known teratogenicity, as well as its capacity to induce spontaneous abortion and fetal/perinatal bleeding coagulation defects at baseline such that the INR is over 1.5 decompensated liver disease