IMPROVING THE ORAL BIOAVAILABILITY OF SULPIRIDE BY SODIUM OLEATE IN RABBITS

To improve the limited oral bioavailability of sulpiride, a dosage for m containing sodium oleate as an absorption enhancer was developed and evaluated using gastric-emptying-controlled rabbits in a cross-over m anner. In addition to the known properties of sodium oleate with respe ct to modifying the permeability of biomembranes, it was found to be c apable of improving the physicochemical properties of sulpiride toward a higher lipophilicity (by ion-pair association) and a higher solubil ity (by micellar solubilization). Nonetheless, the incorporation of so dium oleate with sulpiride as a mixture filled in hard gelatin capsule s failed to increase intestinal absorption, whereas the use of enteric capsules. instead of the-hard gelatin capsules resulted in a signific ant increase (P<0.05) in the oral bioavailability.