Reduced thrombus formation in vivo after administration of pentoxifylline (Trental).

The hamster cheek pouch model of experimental thrombosis in which thrombi are induced in the microvasculature by iontophoretical administration of adenosine diphosphate (ADP) was used to test the antithrombotic potential of pentoxifylline (Trental). Single intraperitoneal injections of 5, 10 and 20 mg/kg pentoxifylline reduced thrombus formation by 20 to 50% from 30 to 105 min following drug administration. The effect of a single application of 10 mg/kg was exceeded significantly (p less than 0.05) by the higher rate of inhibition after repeated injections of the same dose given three times daily. This suggests a residual antithrombotic effect from the preceding administrations.