Two different indomethacin capsules, a commercial one containing fine drug particles and an experimental capsule containing 125-177 microns particles, were employed in this study. The commercial preparation showed faster in vitro dissolution than the experimental one. When administered to humans having normal acidity of the gastric juices, the commercial capsule exhibited higher Cmax and smaller Tmax and mean residence time (MRT) than the experimental one both in fasting and nonfasting states, although the two capsules were equivalent in area under the serum concentration-time curve (AUC). The ingestion of a breakfast delayed the gastrointestinal absorption from both preparations, which resulted in larger Tmax's and MRT's and smaller Cmax's in the nonfasting state. Food, however, did not have any significant effect on the AUC's of the preparations.