FORMULATION AND EVALUATION OF BILAYER TABLET OF ANTIHYPERTENSIVE DRUG

Madhu Rajak*, A. Amal Raj, Rajendra Singh Dhakad and Hakim Singh Rajput

The aim of present study is to prepare bilayer tablets of Losartan Potassium with an immediate release and a sustained release layer. The immediate release layer was prepared using super disintegrant sodium starch glycolate and sustained release layer is formulated with different polymers. The bilayer tablets of losartan potassium were prepared by the direct compression method. The drug, polymers and other excipients used for both immediate (IR) and sustained release (SR) layers were passed through sieve #80 before their use in the formulation. The immediate dose of drug was calculated from total dose of losartan potassium extended release tablet, which is 50 mg. Losartan potassium can be administered once or twice daily with total daily doses ranging from 25 mg to 100 mg. in vitro dissolution was carried out using USP Dissolution testing apparatus type-II (Paddle method; Veego Scientific VDA-8DR, Mumbai, India). Different batches of tablets were prepared varying the different sustaining components that were considered to have significant effect on drug release. These bilayer tablets as well as the powder blends were subjected to various in-process quality control tests for evaluation of their different physical parameters. The release of losartan potassium from fast releasing layer was analyzed by plotting the cumulative percentage of drug release Vs time. It shows an effective initial burst effect from IR layer and released from this layer was completed within 10 minutes. Bi-layer tablet is improved beneficial technology to overcome the limitation of the single layered tablet.