@article {93, title = {Evaluation of Changes in Bleeding Time in Hypertensive Patients on Amlodipine - A Prospective Observational Study}, journal = {International Journal of Pharmacology and Clinical Sciences}, volume = {5}, year = {2016}, month = {June 2016}, pages = {45-48}, type = {Research Articles}, chapter = {45}, abstract = {

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{\textquoteright}s unpaired t-test was used to compare Amlodipine test group with the normotensive control group. Results were expressed as Mean bleeding time {\textpm} SEM. SPSS software version 20 was used for statistical calculations. Results: The mean bleeding time of Amlodipine group was 2.214 minutes {\textpm} 0.028 SEM. The control group had a mean bleeding time of 1.998 minutes {\textpm} 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.

}, keywords = {Amlodipine, Antiplatelet activity, Bleeding time, Hypertension}, doi = {10.5530/ijpcs.5.2.2}, author = {Pallavi Mahadeva Kamath and Suresh Surappla Rudrappa and Arun Suresh and Narendranath Sanji and Shashikala Gowdara Hanumanthareddy and Imran Maniyar} } @article {128, title = {Comparison of In vitro Antioxidant Activity of Olmesartan and Amlodipine}, journal = {International Journal of Pharmacology and Clinical Sciences}, volume = {4}, year = {2015}, month = {Dec 2015}, pages = {90-93}, type = {Research Article}, chapter = {90}, abstract = {

Introduction: Free radical oxidative stress has been implicated in the pathology of a wide variety of clinical disorders. Antioxidants are agents which scavenge the free radicals and prevent the damage caused by them. Angiotensin II receptor blockers used in the treatment of hypertension, have also been reported to protect organs such as kidney and heart. Althoug, the mechanisms of these protective effects are not fully understood, it is generally thought that their antioxidant effects likely play a role. Amlodipine, a calcium channel blocker, seems to exert atheroprotective effects through its antioxidant properties related to its chemical structure and independent of its calcium channel-blocking effect. Though research has proved that olmesartan and amlodipine exhibit antioxidant activity independent of their antihypertensive effects, there are not many in vitro studies to analyse which drug is a better antioxidant. Objective: This in vitro study was done to compare the antioxidant activity of olmesartan and amlodipine. Materials and Methods: In this study, we demonstrated the antioxidant activities of 10 mg/ml stock solutions of olmesartan and amlodipine in vitro. DPPH (1,1 Diphenyl 2-picryl hydrazide) and Nitric oxide free radical scavenging assays were done. Results: Olmesartan showed significant (49.48\%) and consistent free radical scavenging activity by DPPH and Nitric oxide radical scavenging assays. Free radical scavenging activity of amlodipine was more significant (56.89\%) than olmesartan but was inconsistent and non-concentration dependent. Conclusion: Hence this in vitro study has proved that olmesartan has better antioxidant activity than amlodipine.

}, keywords = {Amlodipine, DPPH, Free radicals, Nitric Oxide, Olmesartan, Oxidative Stress}, doi = {10.5530/ijpcs.4.4.4}, author = {Rajathilagam Thiruvengadam and Seethalakshmi Sankar} }