Background: Platelet hyperactivity is a risk factor in hypertensive patients that paves the way to atherothrombosis causing cardiovascular and cerebrovascular events. Counteracting platelet aggregation is an established step in preventing thrombotic events. Calcium channel blockers are one among the recommended antihypertensive agents according to 2013 ESH/ESC (European Society of Hypertension and European Society of Cardiology) guidelines. In addition to lowering blood pressure they are known to have antiplatelet activity. Dihydropyridine class of L-type calcium channel blockers are the most potent group and shares this activity. Anti-platelet aggregatory effect of these agents could supplement its anti-hypertensive property and could prove to be desirable in the treatment of hypertensives with high risk of atherosclerotic and thromboembolic risk. So the present study aims to explore the anti-platelet activity of Amlodipine. Objectives: To evaluate the anti-platelet activity of Amlodipine in hypertensive patients. Methods and Materials: Sixty subjects were enrolled in the study. Test group comprised of thirty patients with essential hypertension, who were prescribed Tab Amlodipine at doses 5 mg or 10 mg once daily orally. Patients included in study group were regularly on Amlodipine for at least one month. 30 normotensive subjects, who are not on any drug affecting platelet function like Aspirin, dipyridamole, statins etc. acted as control group.Duke method of Bleeding time estimation was used to assess changes in Bleeding time. Statistical analysis: Student’s unpaired t-test was used to compare Amlodipine test group with the normotensive control group. Results were expressed as Mean bleeding time ± SEM. SPSS software version 20 was used for statistical calculations. Results: The mean bleeding time of Amlodipine group was 2.214 minutes ± 0.028 SEM. The control group had a mean bleeding time of 1.998 minutes ± 0.036 SEM. The result gave a statistically significant p value of <0.001. Average duration of treatment was 3.683 years. Conclusion: The statistically significant bleeding time observed in Amlodipine group suggest that it has anti-platelet activity.
Key words: Amlodipine, Hypertension, Bleeding time, Antiplatelet activity.