The effects of oleic acid, tolbutamide, and oxyphenbutazone on the binding of warfarin by human serum albumin.

Equilibrium dialysis studies showed that, at low levels, stearate, palmitate and oleate enhanced the binding of warfarin by human serum albumin, but at high levels of FFA, warfarin was displaced. Tolbutamide and oxyphenbutazone separately desplaced warfarin, and this dispplacement was reduced by the presence of low concentrations of oleate while at higher concentrations of oleate displacement occurred. Thus, the binding of warfarin was affected in a complex fashion depending upon the drugs present and the concentration of the FFA.