Formulation and Optimization of Propranolol Bilayer Tablets: A Potential Approach for Effective Management of Hypertension

The purpose of this investigation is to formulate and evaluate the antihypertensive drug propranolol hydrochloride sustained-release bilayer tablets. In this formulation, one layer provides a loading dose through the immediate release of the drug and the other layer provides a maintenance dose for up to 12 h through controlled release. Different quantities of polymers such as Kyron T-314, Hydroxypropyl methylcellulose-K4M, and ethyl cellulose were used to make bi-layer tablets by direct compression. The compatibility study of pharmaceutical excipients was conducted through Fourier transform infrared spectroscopy studies and no interaction was found. The pre-compression parameter for the angle of repose, bulk density, tapped density and compressibility index was assessed on the produced granules and the findings were good. The tablets were evaluated for the post-compression parameters for thickness, hardness, friability and in vitro release studies. In vitro dissolution study was approved out for 12 h using United States Pharmacopeia dissolution apparatus I using phosphate buffer of pH 1.2 and 6.8 as dissolution medium. Hydroxypropyl methylcellulose-K4M and ethylcellulose were used in combination in all formulations but optimized formulation propranolol hydrochloride tablet 4 showed a higher rate of drug release up to 12 h as compared to the other formulation and optimized formulations propranolol hydrochloride tablet 4 follows the Higuchi model with non-fickian diffusion based on regression coefficient of the kinetics data of cumulative drug release from the dosage form.