Salivary free concentrations of anti-epileptic drugs: An evaluation in a routine clinical setting

Mohammed Al Za'abi, Dirik Deleu, Chris Batchelor

Research output: Contribution to journalArticle

23 Citations (Scopus)


Objective: This study was aimed at correlating the salivary and serum free concentrations of anti-epileptic drugs (carbamazepine, phenytoin and sodium valproate) in a population of neurological patients in a routine clinical setting. Method: Twenty-seven paired serum/saliva specimens from 22 patients : 10 for carbamazepine, 8 for phenytoin and 9 for sodium valproate were obtained to study these correlations. Salivary and serum free concentrations of anti-epileptic drugs, anti-epileptic drug dosing history, and associated information were collected prospectively. The salivary and serum free concentrations of the anti-epileptic drugs were simultaneously quantified using fluorescence polarization immunoassay (TDx analyzer). Results: For both carbamazepine and phenytoin there was a strong correlation between the salivary and serum free concentrations, 0.99 and 0.98, respectively. The mean ratio of salivary to serum free carbamazepine concentration was 1.02 ± 0.11 and 0.82 ± 0.15 for phenytoin. A poor correlation between salivary and serum free concentration was observed for sodium valproate (0.70) with a mean ratio of salivary to serum free concentration of 0.48 ± 0.27. Conclusion: Monitoring of free salivary concentrations of anti-epileptic drugs, particularly phenytoin and carbamazepine proved to be a realistic alternative in this routine clinical setting.

Original languageEnglish
Pages (from-to)19-23
Number of pages5
JournalActa Neurologica Belgica
Issue number1
Publication statusPublished - 2003



  • Adults
  • Carbamazepine
  • Epilepsy
  • Phenytoin
  • Saliva
  • Serum
  • Sodium valproate
  • Unbound

ASJC Scopus subject areas

  • Clinical Neurology

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