Eptifibatide was modeled after a component in southeastern pygmy rattlesnake venom and is used in anticoagulation therapies in an effort to reduce the risk of heart attacks; it is used in only severe cases because of the possible side effect of thrombocytopenia, a condition where platelets are unable to aggregate at all.[9][10][11] Eptifibatide binds reversibly to platelets reducing the risk of thrombosis. It is an antagonist of glycoprotein IIb/IIIa.[9]