Arixtra (fondaparinux) is classified as which type of medication?

Arixtra (fondaparinux) is classified as a Factor Xa inhibitor. This classification indicates that it works by specifically inhibiting Factor Xa, which is a crucial component in the coagulation cascade responsible for blood clot formation. By blocking this factor, fondaparinux effectively prevents the conversion of prothrombin to thrombin, thereby reducing the formation of fibrin and limiting clot development.

In contrast, direct thrombin inhibitors specifically target thrombin, the enzyme responsible for converting fibrinogen to fibrin, but do not directly affect Factor Xa. Vitamin K antagonists work by inhibiting the synthesis of vitamin K-dependent clotting factors but do not directly interact with Factor Xa or thrombin. Antiplatelet medications primarily work by preventing platelet aggregation and do not act on the coagulation factors involved in the formation of clots in the same manner as Arixtra. Thus, fondaparinux's specific action on Factor Xa solidifies its classification in this category.