Abstract
In the department of hospital pharmacy of Okayama University Hospital, measurement of serum level of antiepileptic drugs has been conducted since July 1981. We thus surveyed the changes in the number of antiepileptic drugs prescribed over the past 14 years in order to measure the serum concentration. No characteristic change was observed in the age distribution of the patients. The annual number of serum samples and the assay order has gradually increased since 1981. However, the annual number of drug assays per sample were decreased. The frequency of a phenobarbital assay decreased, while the frequency of a valproic acid assay increased. Prescription containing more than 3 drugs decreased while those with only one drug increased. Phenobarbital in monopharmacy therapy shifted to valproic acid. In polypharmacy therapy, phenytoin was mainly prescribed. In polypharmacy therapy, the prescription rate of phenobarbital or primidone decreased, while the rate of valproic acid or carbamazepine increased. Moreover, an increase in various combinations of antiepions of antiepileptic drugs was observed in polypharmacy therapy. Based on these findings, it was suggested that the pharmacological therapy for epilepsy had thus changed from polypharmacy therapy to monopharmacy therapy, mainly due to the increased use of valproic acid.
