COMPARATIVE IN VITRO DISSOLUTION STUDY OF LOSARTAN POTASSIUM MARKETED TABLETS IN FOUR DIFFERENT DISSOLUTION MEDIA BY VALIDATED ANALYTICAL METHOD

Abstract

There are only 22 pharmaceutical companies out of 151 in Bangladesh producing quality product maintaining the cGMP, where mor e than 40 companies manufacturing Losartan Potassium 50 mg tablets. So, the clinicians and pharmacists are facing difficulty to choose a suitable brand or alternative use. The aim of the present study was to predict the bioequivalence of four top ranked brands of Losartan Potassium tablets marketed in Bangladesh using In Vitro tests. The In Vitro dissolution study was carried out with the five brands of 50 mg Losartan Potassium tablets according to FDA dissolution method. The process was done for 12 tablets of each brand; using 900 ml of pH 1.2 0.1 N HCl, pH 4.5 Acetate Buffer, pH 6.8 Phosphate Buffer and water separately as dissolution media; 50 rpm as rotation speed; 37°C ± 0.5°C as media temperature; 10, 15, 20, 30, 45 and 60minutes as sample collection time points. The results were carried out by interpreting data on the equations of Dissolutio n Efficiency (DE), Difference Factor (f1), Similarity Factor (f2). There were significant differences in the dissolution profiles of the five brands specially when considered according to different media. In pH 1.2 0.1 N HCl all brands showed poor drug release but most were close to innovator brand, but in pH 4.5 Acetate Buffer was unlike due to decrease of ionic strength by media, which affect preferably to innovator brand. pH 6.8 Phosphate Bu ffer and water gave best results for drug release of most of the brands and proved reliable to claim RRR, SSS and NNN as bioequivalent and interchangeable with each other as well as with the innovator brand. The BBB showed poor dissolution profile, which will likely result in poor bioavailability. The results show the need for constant monitoring of new brands of Losartan Potassium introduced into the drug market to ascertain bioequivalence and conformity with pharmacopoeia standards.