Preparation and evaluation of slow-release pan-coated indomethacin granules

Granules containing indomethacin crystals are coated with Eudragit solutions of different RL/RS ratios using a pan coating technique. The process is reproducible with regard to drug content, inexpensive and the formed granules were directly compressed into tablets. In vitro release of indomethacin from coated granules, tablets and capsules was studied as a function of different ratios of Eudragit RL/RS in the coating solution. The release of the drug was significantly reduced by the coating process in comparison with a formulation made from uncoated granules, prepared using 10 per cent gelatin solution as a binder. Release data were found to follow a diffusion-controlled model.