aprotinin

:  a polypeptide with protease-inhibiting properties formerly used to reduce blood loss and preserve platelet function during heart surgery but now withdrawn from use due to safety concerns Based on our data, we therefore believe that additional concern is now warranted regarding the long-term safety of aprotinin among patients undergoing coronary artery bypass surgery.—Dennis T. Mangano et al., The Journal of the American Medical Association, 7 Feb. 2007