Phenytoin penetration into brain after administration of phenytoin or fosphenytoin

Nancy Y. Walton, Basim M. Uthman, Karim El Yafi, Jae Moon Kim, David M. Treiman

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


Purpose: This study was designed to measure the brain penetration of phenytoin (PHT) after intravenous (i.v.) administration of either standard PHT or fosphenytoin (FPHT), a PHT prodrug. The study was formulated to answer the question whether the time required for FPHT to be convened to PHT in the bloodstream would delay the accumulation of PHT in brain. Methods: Four rats were sampled at various times after intravenous infusion of 30 mg/kg PHT i.v. or 30 mg/kg PHT equivalents of FPHT i.v. PHT was measured in serum, protein- free ultrafiltrate, and in brain, by using high-performance liquid chromatography. Results: Although the initial PHT-free fraction was significantly higher for FPHT-treated rats than it was for PHT-treated rats, brain PHT levels were significantly reduced after infusion of FPHT. Conclusions: When FPHT is used for treatment of generalized status epilepticus, it should be anticipated that lower initial brain PHT levels will be achieved than are typically found with standard PHT.

Original languageEnglish (US)
Pages (from-to)153-156
Number of pages4
Issue number2
StatePublished - 1999
Externally publishedYes


  • Brain
  • Fosphenytoin
  • Phenytoin
  • Protein binding
  • Rats

ASJC Scopus subject areas

  • Neurology
  • Clinical Neurology


Dive into the research topics of 'Phenytoin penetration into brain after administration of phenytoin or fosphenytoin'. Together they form a unique fingerprint.

Cite this