Thrombophilic disorders that predispose patients to develop blood clots can be life-threatening and result in a large economic burden on healthcare expenditures. Venous Thromboembolism(VTE) (deep vein thrombosis and pulmonary embolism) are the third leading cause of death in the United States. ProteinCdeficiency is a common thrombophilic condition that affects an estimated 1 in 400 Americans. Zymogen Protein C (ZPC) is the precursor to Activated Protein C (APC), a pivotal endogenous anticoagulant in human blood. Patients with protein C deficiency who have roughly half the normal level of proteinC are estimated to be at 10-fold increased risk of VTE. We describe the use of protein C concentrate (Ceprotin®, Baxter, Deerfield, IL) in a patient with protein C deficiency and with a previous pulmonary embolism who developed a life-threatening gastrointestinal bleed after polypectomy. The patient is a 75-year-old male at very high risk for deep vein thrombosis and possible lung emboli. He has heterozygous Protein C deficiency (50%) and heterozygosity for the prothrombin gene G20210A mutation. During a routine colonoscopy, a large 3 cm cecal polyp was identified and resected. Eight days post-procedure while performing abdominal exercise he developed a life-threatening GI bleed originating from the polypectomy site as his warfarin was becoming therapeutic on a Low Molecular Weight Heparin (LMWH) periprocedural bridge. The patient's warfarin was reversed with vitamin K, and LMWH and warfarin were discontinued. To prevent thrombosis, he was started on ZPC until anticoagulation could be safely restarted. During endoscopy, the bleeding site was treated with an injection of 1:10,000 dilution of epinephrine, followed by cauterization and placement of endoclips (4 metal staples). Three days after endoscopic repair LMWH was restarted with warfarin. Sixteen months post-bleed, the patient remains on life-long warfarin without further episodes of bleeding or thrombosis. Zymogen Protein C concentrate (Ceprotin®, Baxter Deerfield, IL) should be strongly considered for peri-procedural management of any patient with protein C deficiency and previous thromboembolism.