Lih-Chi Chen

The present study was conducted to evaluate the effects of Paeoniae Radix (PR), one of the most famous tonic traditional Chinese medicines, on the pharmacokinetics of carbamazepine (CBZ) in rats and to determine the possible interactions between PR and CBZ. The significant decrease in Tmax indicated that simultaneous oral administration of PR contributed to more rapid absorption of CBZ. It is suggested that the faster absorption of CBZ might lead to the rapid onset of its clinical effect. There were no significant differences in maximum concentration (Cmax), area under the plasma concentration–time curve (AUC), half-life (t1/2), mean residence time (MRT), clearance/bioavailability (CL/F), and apparent volume of distribution/bioavailability (Vd/F) of CBZ between the two groups, showing that PR did not significantly affect the absorption extent, distribution, metabolism, and elimination of CBZ. A significant decrease in protein binding rate was found when CBZ was coadministered with PR. Further studies are in progress to clarify the clinical significance and the mechanism underlying the effects of PR on the protein binding of CBZ observed in the present study.

Background: Phenytoin (PHT), one of the most widely prescribed antiepileptic drugs, has been reported to be associated with numerous drug–drug interactions. However, there are far fewer reports abou...

Objective: Studies on antiepileptic drug utilization are important for the optimization of drug therapy and drug control. The present study was to evaluate the drug utilization pattern of standard antiepileptic drugs and traditional Chinese medicines (TCMs) in the treatment of different types of epilepsy in a general hospital in Taiwan. Method: The epileptic patients under antiepileptic drug treatment at Veterans General Hospital-Taipei were considered in the analysis. Current diagnosis was obtained by the neurologist in charge of the patient. All patients were interviewed by standard questionnaire designed to provide specific information on the types of antiepileptic drugs and details of their use. The questionnaire also sought to determine whether TCMs were used, and whether patients were using TCMs in combination with hospital standard treatment. The results were analysed by descriptive statistics. Results: 729 patients with epilepsy definitely diagnosed were analysed in the study. 445 patients (61·04%) were prescribed with one antiepileptic drug. Combinations of two antiepileptic drugs were prescribed to 261 patients (35·80%), and combinations of three or more antiepileptic drugs to 23 patients (3·16%). A total of 1039 antiepileptic drugs was prescribed, corresponding to an average 1·42 drugs per patient. The most frequently prescribed antiepileptic drug was carbamazepine (56·93%), followed by phenytoin (31·96%), valproate (30·73%) and clonazepam (14·13%). Among the 729 epileptic patients, 83·68% used standard antiepileptic drugs alone, 16·32% used antiepileptic drugs in combination with TCMs. Conclusion: Monotherapy is the type of therapy most frequently used in all types of seizures. The selection of antiepileptic drugs is based on efficacy for specific seizure types and epileptic syndromes. The most frequently prescribed antiepileptic drug was carbamazepine, followed by phenytoin, valproate and clonazepam. As some of the patients used TCMs for treatment of epilepsy even when scientific medicine has been provided, further studies on the possible interactions between TCMs and antiepileptic drugs are in progress.