Formulation and Development of Bilayer Floating Tablets of Nifedipine

The aim of the present research work was to develop and formulate a bilayer floating sustained release tablet of Nifedipine. Nifedipine is an antihypertensive agent. Surface solid dispersion of Nifedipine was prepared by solvent evaporation method with different super disintegrants as a polymer for improvement of solubility resulting in improved bioavailability. Bilayer consists of two layers, immediate-release layer, and second sustained release layer, compressed in the single unit dosage form. The immediate-release layer contains surface solid dispersion of Nifedipine. The floating sustained release layer also contains surface solid dispersion of Nifedipine, HPMC K100M & HPMC K15M as sustained release polymer. The floating properties of the tablets were achieved by the use of sodium bicarbonate & citric acid which generate the gas upon contact with gastric fluid. The immediate-release layer releases the drug immediately and starts the onset of action and the floating sustained release layer floats on gastric fluid for upto12 hours and releases the drug in a sustained manner, subsequently, it prolongs the duration of action.