1. The effectiveness of the inclusion product of piroxicam with beta-cyclodextrin was compared to that of free piroxicam on inflammatory reactions by using three experimental inflammatory models in rats. 2. The inclusion compound showed anti-inflammatory effects similar to those of simple piroxicam on granuloma tissue formation and arthritis induced by complete Freund adjuvant. 3. In carrageenin-induced pleurisy, the piroxicam beta-cyclodextrin reduced leukocyte mobilization more intensely than non-complexed piroxicam. 4. These results suggest that beta-cyclodextrin is a useful tool for improving the efficacy of piroxicam.