CONTROLLED RELEASE FORMULATION DEVELOPMENT AND EVALUATION OF FELODIPINE MATRIX TABLETS BY USING HYDROPHOBIC POLYMERS

Felodipine is a long-acting 1, 4-dihydropyridine calcium channel blocker, used to control hypertension by selective action on peripheral resistance. The conventional felodipine tablet gives a rather high peak and comparatively low trough levels, due to rapid absorption and distribution. More sustained plasma concentrations might thus produce a more even effect on blood pressure.  The main aim of the study was to improve dissolution rate of the dosage form in a controlled manner over extended period of 24 hrs. Matrix tablets were prepared by direct compression method,using hydrophobic polymers like Glyceryl monostearate and Carnauba wax. The prepared formulations were evaluated for hardness, thickness, weight variation, friability and in-vitro dissolution studies. Among all the formulations F8 was selected as optimized formulation based on the evaluation parameters and in-vitro release profile of 100% drug release for 24 hrs. The FTIR and DSC results of optimized formulation showed no drug-excipient interaction. For optimized formulation(F8), the drug release mechanism was explored and explained by zero-order (r²=0.984), first-order (r²=0.947), Higuchi (r²=0.967) and Korsmayer-peppas (r²=0.982 & n=0.855) equations, which explained the drug release follows zero-order and is fit for Higuchi equation & mechanism was anomalous diffusion i.e diffusion and erosion.