Bovine-source topical thrombin may be associated with abnormal hemostasis, ranging from asymptomatic laboratory alterations to severe bleeding and/or thrombosis. Abnormalities appear to be immunologically mediated. Repeated applications increase risk. Re-exposure of patients who develop antibodies to bovine thrombin preparations should be avoided. May potentially contain infectious agents which could transmit disease. Use caution in hypersensitivity to snake proteins (potential for allergic reaction). Do not use in infection. Use caution in areas of contamination. For topical use only. Do not inject intravenously or intra-arterially (intravascular clotting, possibly leading to death, may occur following injection). Powder and solution formulations may be used in combination with absorbable gelatin sponges.