Formulation Development and Evaluation of Bi-Layered Tablet Containing Diuretic and Anti-Hypertensive Agent
The aim of present study was to develop a Bi-layered tablet for management of hypertension using hydrochlorothiazide (HCTZ) in combination with propranolol HCl (Prop.Hcl). Bi-layered tablets were prepared using direct compression method by wet granulation technique consisting an immediate released layer and the sustained released layer. The tablets prepared were evaluated for their physico-chemical properties. Formulation (F4) prepared with 1% cross carmellose sodium (CCS), released the drug i.e. hydrochlorothiazide (HCTZ) content of the immediate layer at the end of the 45 minutes. Formulation (F8) prepared from intragranulation techniques in which combination of both the polymer concentrations in sustained layer showed the synergistic effect and the release rate of the total drug i.e. propranolol HCl content sustains till the end of 12 h respectively. The mechanism of drug release was regarded as anomalous diffusion of drug from the matrix. The optimized formulation (F8) was subjected to short term stability studies as per ICH guidelines and formulations were found to be stable after a 3 month study. It can be concluded that, the optimized formulation (F4) containing 1% CCS in Immediate layer releases the drug hydrochlorothiazide within 45 min & with combination of both polymers with an individual concentration of 7.5% in Sustained layer sustains the release of the drug up to 12 h.