CSF CONCENTRATIONS AND SERUM PROTEIN BINDING OF CARBAMAZEPINE AND CARBAMAZEPINE‐10, 11‐EPOXIDE IN EPILEPTIC PATIENTS

Abstract

1 Serum and CSF samples of patients receiving chronic carbamazepine treatment were analysed. 2 Daily fluctuations in serum levels of carbamazepine and carbamazepine-10, 11-epoxide did not appear to be related to the dosage schedule, but some patients tended to have lower fluctuations when the carbamazepine was given more frequently. 3 The epoxide/carbamazepine serum ratios varied greatly from patient to patient, and also fluctuated during the day for the same patient. 4 Carbamazepine and carbamazepine-10, 11-epoxide were present in CSF in concentrations ranging from 19 to 34% and 26 to 71% of the serum concentrations, respectively. 5 There was a significant relationship between the free fraction of both drugs evaluated in vivo and the CSF/serum ratios. 6 The need for a careful evaluation of the possible clinical effect of the epoxide is stressed.