GI bleeding is a relative contraindication to heparin administration and warrants investigation for an underlying anatomic abnormality. Heparin can be reversed rapidly by infusion of protamine sulfate. Warfarin inhibits conversion of vitamin K to its active from. More serious bleeding should be managed in the same manner as that for vitamin K deficiency with infusion of FFP or vitamin K, depending on the urgency of the situation. Drug interaction should be considered.
Warfarin is contraindicationted in the first trimester of pregnancy because of teratogenicity.
Tranexamic acid can inhibit activation of plasminogen.