PHARMACOKINETICS OF THE TOTAL TRITERPENIC FRACTION OF CENTELLA-ASIATICA AFTER SINGLE AND MULTIPLE ADMINISTRATIONS TO HEALTHY-VOLUNTEERS - A NEW ASSAY FOR ASIATIC ACID

A new HPLC assay method was used to investigate the pharmacokinetics of asiatic acid after oral administration of the total triterpenic fraction of Centella asiatica in single doses (30 or 60 mg) and after a 7-day treatment (30 or 60 mg twice daily). Twelve healthy volunteers received each treatment following a randomized cross-over design with trials separated by a 3-week interval. The time of peak plasma concentration was not affected by dosage difference or by treatment scheme. Differences in peak plasma concentration and area under the concentration vs. time curve from 0 to 24 h (AUC0-24) calculated after 30 or 60 mg administration (single dose) were accounted for by the different dose regimen. However, after chronic treatment with both 30 and 60 mg, peak plasma concentrations, AUC0-24 and halflife were significantly higher than those observed after the corresponding single dose administration. This phenomenon could be explained by a metabolic interaction between asiatic acid and asiaticoside, which is transformed into asiatic acid in vivo. © 1990.