The influences of fasting on elimination of sulfonylurea (SU) compounds from plasma were investigated in rabbits after intravenous administration. When SU compounds were intravenously given under fasted conditions, their elimination from plasma decreased more significantly than that under feeding conditions. A marked effect was found in chlorpropamide among SU compounds studied. A possible reason of the decrease of elimination rate constants of SU compounds in fasted rabbits was studied using chlorpropamide. The decreased renal tubular secretion and the increased renal tubular reabsorption of chlorpropamide observed under fasted conditions were considered to be possible reasons of the decreased elimination of SU compounds from plasma.
