COMPARISON OF EFFECT OF LOCALLY AVAILABLE BRANDS OF CLOPIDOGREL ON PLATELET AGGREGATION IN PATIENTS WITH CORONARY ARTERY DISEASE
AbstractBackground: Anticoagulant effect of clopidogrel is of utmost importance in coronary artery disease,especially in prevention of coronary stent thrombosis. Recently, many new local brands of clopidogrelhave been launched, with unknown efficacy. This study was conducted with the aim to compare twolocally prepared clopidogrel brands, in terms of the effect of a loading dose of 600 mg on inhibition ofplatelet aggregation in patients with coronary artery disease. Methods: This was a double blindrandomised study. Sample population consisting of 35 patients, were admitted at Lady ReadingHospital, Peshawar, for the management of coronary artery disease. Baseline platelet aggregation of allthese patients was measured. These patients were divided in two groups randomly. Group-A consistingof 18 patients was given brand ‘A’ clopidogrel 600 mg, while Group-B consisting of 17 patients wasgive brand ‘B’ of clopidogrel 600 mg. The platelet aggregation of both groups was then measured atbaseline, and at 2, 4, and 6 hours after taking the loading dose of 600 mg. Results: Platelet aggregationtime at baseline in Group-A was 2.61±2.28 sec. and in Group-B it was 2.24±1.52 sec. (p=0.57). After 2hours of clopidogrel administration in Group-A the platelet aggregation time was 1.44±1.58 sec. and inGroup-B it was 1.53±1.107 sec. (p=0.85). Platelet aggregation time after 4 hours in Group-A was0.28±0.57 sec. and in Group-B 1.06±1.03 sec. (p=0.009), and after 6 hours it was 0.00±0.00 sec. inGroup-A and in Group-B it was 0.59±0.71 sec. (p=0.001). Conclusion: The two brands of clopidogrelhad a significant difference in their effect on inhibition of platelet aggregation. Different brands ofclopidogrel may not be equally effective.Keywords: Platelet Aggregation, Clopidogrel, Coronary Artery Disease
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