Pulsatile Delivery System for Antihypertensive Drug

The purpose of present work was to formulate an oral pulsatile drug delivery system to achieve time release of felodipine, based on chronopharmaceutical approach for the treatment of hypertension. System was prepared in the form of two layered tablets by press coating method. Active rapid release core tablet contains physical mixtures of felodipine with novel micro encapsulated solubilizers like Sepitrap 4000, Sepitrap 80 formulated by direct compression method. From dissolution studies, core tablet formulated with these novel surfactants released whole amount within 15min and 30min respectively. This dissolution enhancement and fast release was attributed to decrease in crystallinity of felodipine as was found from XRD data. Dry coating of optimized RRCT was done by using different grades of hydroxy propyl methyl cellulose (HPMC) E5, E15 and E50. On the basis of in-vitro release profile it was found that the optimized formulation F6 showed the lag time of 7.5h which showed compliance with chronotherapeutic objective of hypertension. Solid state characterization (FTIR, XRD studies) indicated that there was decrease in crystallinity of the drug with no interaction between drug and excipients.