Effects of Simultaneous Administration of Drugs on Absorption and Excretion. V. Effect of Phenylbutazone on Antibacterial Activity and Distribution of Sulfadimethoxine in Rabbits

Abstract

The antibacterial activities of sulfadimethoxine in rabbit plasma were significantly increased by concomitant injection of phenylbutazone. On the other hand, the levels of unchanged sulfadimethoxine determined by chemical assay in rabbit plasma were significantly reduced by concomitant injection of phenylbutazone. These results suggest that phenylbutazone increases the transfer of sulfadimethoxine from plasma to tissues in rabbits.