Influence of Piperine on the Pharmacokinetics of Curcumin in Animals and Human Volunteers

The medicinal properties of Curcumin obtained from Curcuma longa L. cannot be utilised because of poor bioavailability due to its rapid metabolism in the lover and intestinal wall. In this study, the effect of combining piperine, a known inhibitor of hepatic and intestinal glucuronidation, was evaluated on the bioavailability of Curcumin in rats and healthy human volunteers. When Curcumin was given alone, the dose 2g/kg to rats, moderate serum concentrations were achieved over a period of 4 h. Concomitant administration of piperine 20mg/kg increased (P < 0.02), and he bioavailability was increased by 154%. On the other hand in humans after a dose of 2g Curcumin alone, serum levels were either undetectable or very low. Concomitant administration of piperine 20mg produced much higher concentrations from 0.25 to 1h post drug (P < 0.01 at 0.25 and 0.5h; P < 0.001 at 1h), the increase in bioavailability was 2000%. The study shows that in the dosages used, piperine enhances the serum concentrations, extent of absorption and bioavailability of curcumin in both rats and humans with no adverse effects.