Formulation and Evaluation of Sustained Release Mucoadhesive Atenolol Tablets for Gastric Retention

Abstract

An oral sustained release gastroretentive dosage form comes out as better alternative for drugs having narrow absorption window. Atenolol conventional tablets have been reported by many scientists to exhibit poor oral bioavailability and fluctuations in plasma drug concentration. This results, either in precipitation of side effects or reduction in drug concentration at the target site. Thus objective of present study was to develop, optimize and evaluate a gastroretentive, mucoadhesive tablet for sustained release. A 22 factorial design was employed to systematically study the drug release profile and bioadhesive strength. Sodium carboxymethyl cellulose (CMC) and carbopol 934P were selected as independent variables. Tablets were prepared by direct compression and were evaluated for tablets characteristics, swelling study, adhesion strength and percent drug released. Optimized formulation was compared with marketed formulation (ATEN-50). In vitro wash off test was applied to study the gastroretentive behavior.Tablets prepared show good tablet characteristics, optimum swelling behavior and high adhesion strength. The optimized batch follows zero order drug release profile with non fickian transport mechanism. The mucoadhesion time for optimised batch (M4) was found to be more than four hours and compared with plain tablet which was found to be very less (less than half hour).Thus, the gastroretension by mucoadhesion proven to be a potential tool for drug atenolol which improves its bioavailability with reduction in dosing frequency and dose related side effects.