11-Dehydro-thromboxane B2 - 13 C 5 is 13 C labeled 11-Dehydro-thromboxane B2. 11-Dehydro-thromboxane B2 is a platelet hemagglutinin. Thromboxane inhibition was assessed by urinary excretion levels of 11-Dehydro-thromboxane B2. 11-Dehydro-thromboxane B2 can be used in the study of atherosclerotic thrombosis.