The influence of polytherapy on the relationships between serum carbamazepine and its metabolites in epileptic children

Research output: Contribution to journalArticlepeer-review

11 Scopus citations

Abstract

The influence of polytherapy on the relationships between the age, weight, carbamazepine (CBZ) dose, total clearance and intrinsic clearance, with concentrations, concentration ratios and level/dose ratios of CBZ, carbamazepine-10,11-epoxide (CBZ-E) and trans-10,1 l-dihydroxy-10,11-dihydro-carbamazepine (CBZ-H) are investigated. Three groups of patients with CBZ monotherapy, or receiving CBZ polytherapy by taking CBZ and valproic acid (VPA) or CBZ plus other antiepileptic drugs (AEDs) were studied. The significant correlations between serum CBZ concentrations and CBZ dose in patients taking CBZ alone were no longer significant in patients with polytherapy and the positive associations between serum CBZ-E concentrations and CBZ dose were lost in patients with CBZ + VPA. Only the concentrations of CBZ-H had significant correlations with CBZ dose in all three groups of patients. Results from this relationship study indicate a heteroinduction effect of other AEDs on CBZ metabolism and a relatively weak influence on CBZ-E elimination. Data also suggest that there is a block in the biotransformation from CBZ-E to CBZ-H in patients taking CBZ + VPA, presumably caused by the inhibition effect of VPA on epoxide hydrolase. Therapeutic drug monitoring of CBZ will benefit from the knowledge obtained from the relationship study.

Original languageEnglish (US)
Pages (from-to)257-269
Number of pages13
JournalEpilepsy Research
Volume17
Issue number3
DOIs
StatePublished - Mar 1994

Keywords

  • Antiepileptic drugs
  • Carbamazepine
  • Carbamazepine diol
  • Carbamazepine epoxide
  • Epileptic children
  • Valproic acid

ASJC Scopus subject areas

  • Neurology
  • Clinical Neurology

Fingerprint Dive into the research topics of 'The influence of polytherapy on the relationships between serum carbamazepine and its metabolites in epileptic children'. Together they form a unique fingerprint.

Cite this