- Active thrombophlebitis, thromboembolism, hypercoagulability states, bleeding, or use of anti-coagulation therapy (including lovenox, warfarin, or anti platelet agents such as aspirin [with the exception of low dose ASA ~ 81 mg/d] , clopidogrel, ticlopidine, dipyridamole, and other agents used to induce long-acting platelet dysfunction). Patients with a history of deep venous thrombosis may participate if successfully treated, completely resolved, and no treatment has been given for greater than 4 months.