Skip to main content
British Journal of Clinical Pharmacology logoLink to British Journal of Clinical Pharmacology
. 1974 Feb;1(1):59–66. doi: 10.1111/j.1365-2125.1974.tb00207.x

Inhibition of phenytoin metabolism by sulthiame in epileptic patients

G W Houghton, A Richens
PMCID: PMC1402405  PMID: 22454870

Abstract

1 Measurements have been made of steady state serum phenytoin concentration, serum half-life of 14C-labelled phenytoin, and the urinary ratio of the major metabolite of phenytoin to the unchanged drug (p-HPPH: DPH ratio) in epileptic patients on and off sulthiame therapy.

2 Starting sulthiame treatment produced an increase in serum phenytoin concentration, a prolongation of the half-life and an increase in the p-HPPH: DPH ratio. The total urinary output of phenytoin plus p-HPPH was unaltered by sulthiame.

3 The results indicate that sulthiame or one of its metabolites inhibits the parahydroxylation of phenytoin by hepatic enzymes.

Full text

PDF
62

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Arnold K., Gerber N. The rate of decline of diphenylhydantoin in human plasma. Clin Pharmacol Ther. 1970 Jan-Feb;11(1):121–134. doi: 10.1002/cpt1970111121. [DOI] [PubMed] [Google Scholar]
  2. Atkinson A. J., Jr, Shaw J. M. Pharmacokinetic study of a patient with diphenylhydantoin toxicity. Clin Pharmacol Ther. 1973 Jul-Aug;14(4):521–528. doi: 10.1002/cpt1973144part1521. [DOI] [PubMed] [Google Scholar]
  3. Bochner F., Hooper W. D., Tyrer J. H., Eadie M. J. Effect of dosage increments on blood phenytoin concentrations. J Neurol Neurosurg Psychiatry. 1972 Dec;35(6):873–876. doi: 10.1136/jnnp.35.6.873. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. GORDON N. THE USE OF OSPOLOT IN THE TREATMENT OF EPILEPSY. Epilepsia. 1964 Mar;5:68–73. doi: 10.1111/j.1528-1157.1964.tb04347.x. [DOI] [PubMed] [Google Scholar]
  5. Hansen J. M., Kristensen M., Skovsted L. Sulthiame (Ospolot) as inhibitor of diphenylhydatoin metabolism. Epilepsia. 1968 Mar;9(1):17–22. doi: 10.1111/j.1528-1157.1968.tb04954.x. [DOI] [PubMed] [Google Scholar]
  6. Houghton G. W., Richens A. Proceedings: Inhibition of phenytoin metabolism by sulthiame. Br J Pharmacol. 1973 Sep;49(1):157P–158P. [PMC free article] [PubMed] [Google Scholar]
  7. INGRAM T. T., RATCLIFFE S. G. Clinical trial of Ospolot in epilepsy. Dev Med Child Neurol. 1963 Jun;5:313–315. [PubMed] [Google Scholar]
  8. Kutt H., Haynes J., McDowell F. Some causes of ineffectiveness of diphenylhydantoin. Arch Neurol. 1966 May;14(5):489–492. doi: 10.1001/archneur.1966.00470110033004. [DOI] [PubMed] [Google Scholar]
  9. Olesen O. V., Jensen O. N. Drug--interaction between sulthiame (Ospolot (R)) and phenytoin in the treatment of epilepsy. Dan Med Bull. 1969 May;16(5):154–158. [PubMed] [Google Scholar]

Articles from British Journal of Clinical Pharmacology are provided here courtesy of British Pharmacological Society

RESOURCES