Formulation and in vitro Characterization of Time Release Tablets of Propranolol Hydrochloride

The objective of this investigation was to prepare and evaluate propranolol hydrochloride time release tablets using press coating technique. The time release tablet consisted of two layers, a core tablet containing the active ingredient and an outer cell coating. The core tablet was prepared with the active ingredient using conventional method. Press coated optimized tablet was formulated using different ratios of ethyl cellulose and hydroxypropyl methylcellulose K4M. The coated tablets were evaluated by estimating the physical attributes, drug content, X-ray powder diffraction, Fourier-transform infrared spectroscopy and in vitro drug release profile. Based on the evaluation parameters formulation F10 showed a 6 h release lag time. The release pattern of F10 formulation fulfilled the circadian variation matching the chronotherapeutic objective of hypertension.