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 drugexcipient interaction. For optimized formulation(F8), the drug release mechanism was explored and explained by zero-order (r=0.984), first-order (r=0.947), Higuchi (r=0.967) and Korsmayer-peppas (r=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. INTRODUCTION: Oral solid formulations hold a high potential as they serve to be most convenient for the administration of drugs. More than 50% of drug delivery systems available in the market are oral drug delivery systems. They offer convenience and ease of administration, greater flexibility in dosage form design and ease of production and low cost 1, . Controlled release (CR) technology has rapidly emerged over the past three decades as a new interdisciplinary science that offers novel approaches to the delivery of bioactive agents into the systemic circulation for a prolonged period at a predetermined rate. The choice of drug to be delivered, clinical needs, and drug pharmacokinetics are some of the important considerations in the development of CR formulations, in addition to the relationship between the rates of drug release from the delivery system to the maximum achievable rate of drug absorption in to the systemic circulation 3, 6, . Correspondence to Author: