Effects of Ticlopidine on Platelet Function and Blood Coagulation

Summary

A double blind study was performed on 20 atherosclerotic patients. A placebo was administered to one group of 10 patients (group A) and ticlopidine (500 mg/day) was administered to another group of 10 patients (group B) for one month. ADP and collagen-induced platelet aggregation (PA), platelet malondial-deyde (MDA) produced by thrombin stimulation and plasma beta-thromboglobulin (βTG) levels, prothrombin time, activated partial thromboplastin time (APTT) fibrinogen, antithrombin (AT) III, fibrin(ogen) degradation products, alpha₂-antiplasmin and plasminogen were evaluated in both groups before and after treatment. No changes in PA, MDA and βTG were seen in group A. Group B showed a significant decrease of PA, βTG and a significant increase of MDA. No changes on blood coagulation data were seen in either group. This study suggests that ticlopidine is able to inhibit platelet function in vivo.

Keywords

Blood coagulation - Platelet function - Ticlopidine

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