Formulation and evaluation of matrix tablets of ramipril using hydrophilic polymer (HPMCK15M) and karayagum

Ramipril is an angiotensin-converting enzyme (ACE) inhibitor, used to Hypertension (high blood pressure) and congestive heart failure (CHF). These inhibitors relax (arterioles) the muscles around small arteries. They expand the arterioles and allow to blood flow through more easily. This reduces blood pressure (B.P). Controlled release matrix tablets of Ramipril were prepared by using three polymers, one of the hydrophilic polymer hydroxy propyl methyl cellulose K15M (HPMCK15M) with four concentrations (drug: polymer ratios-1:0.25, 1:0.50, 1:0.75, 1:1), PVPK300, and Karayagum by wet granulation method. The granules were evaluated for bulk density, tapered density, bulkiness, angle of repose, Hausners ratio and compressibility index. In vitro release studies revealed that Ramipril formulation with high proportion of HPMCK15M (1:1) was able to control the drug release for 12 hours (85.4±1.26). The in-vitro drug release data, curve-fitting kinetic analysis and all the formulations followed the mechanism of erosion and diffusion. All the formulations were subjected to stability analysis for stored at 45°±2°C, 75±5%RH up to 45 days.