Kinetic studies on drug disposition in rabbits. III. Effect of tolbutamide on renal excretion of sulfamethizole.

The analysis using the perfusion limited model showed that the elimination kinetics of sulfamethizole in the presence of tolbutamide could be described by the mutual displacement of plasma protein binding of both drugs and the competitive inhibition of the tubular secretion of sulfamethizole by the unbound concentration of tolbutamide in renal vein.