Design and evaluation of three layer matrix tablet of Losartan potassium capped with Eudragit and HPMC combination

In the present investigation concern the formulation and evaluation of trilayer matrix tablets of losartan potassium (LP). Losartan potassium is an angiotensin-II receptor antagonist drug used mainly to treat high blood pressure. The biological half-life and bioavailability of losartan is very poor. Therefore, by using trilayer matrix tablet, we can improve the bioavailability of losartan using combination of different polymers and improve the patient compliance by reducing the frequency of administration. In the trilayer matrix tablets by using polymeric matrix to control the release of an active ingredient is one of the simple ways of formulating dosage form, and has been widely studied for various drug molecules. Trilayer matrix tablets comprised of three layers, a middle layer containing drug capped with combination of different polymers. The powder blend prepared fortrilayer tablet formulations were subjected to FT-IR for any interaction. The tablets were prepared by direct compression method.The resultsshowed that higher the concentration of HPMC in upper and lower layer were better in sustaining therelease of the drug. The best sustained release profile in case of trilayermatrix tablets of losartan potassium was seen in F3 followed by F2,F6,F1,F5 and F4. The release data was fitted to various mathematical models such as Higuchi, first and zero order to evaluate kinetics and mechanism of drug release and it was observed that drug release was best fitted to Zero order and Higuchi model. All formulations were subjected for stability studies at different temperatures for 8 weeks and no significant change was observed.