Studies on interactions between traditional herbal and western medicines. V. effects of Sho-saiko-to (Xiao-Cai-hu-Tang) on the pharmacokinetics of carbamazepine in rats.

摘要: The possibility of pharmacokinetic interactions between Sho-saiko-to extract powder (TJ-9), the most widely used traditional Chinese herbal (Kampo) medicine in Japan, and carbamazepine (CBZ), an important anti-epileptic drug, was examined rats. There no significant difference protein binding CBZ serum obtained before after single oral administration TJ-9. addition TJ-9 to normal hepatic microsomes inhibited CBZ-10,11-epoxylase activity a concentration-dependent manner. Liver weight, amounts P450 cytochrome b(5) formation carbamazepine-10,11-epoxide (CBZ-E), active metabolite CBZ, by were not influenced 2-week repeated pretreatment with (1 g/kg/d), although pretreatments phenobarbital (80 mg/kg/d, i.p.) significantly increased these parameters. simultaneous g/kg) decreased peak plasma concentration area under concentration-time curve CBZ-E, lengthened time reach CBZ. Two-week TJ-9, however, did affect profile or any parameter CBZ-E. Also, delayed gastric emptying. These results indicated that rats gastrointestinal absorption at least part, delaying emptying, without affecting metabolism