Phenytoin (II): The Wrong Drug for the Schizophrenic

Fatal Forty DDI: phenytoin, quetiapine, CYP3A4
  • Melisa N. Weingarten
  • Juraj Sprung
  • Toby N. Weingarten


This case discusses the pharmacokinetic interaction between quetiapine and phenytoin, resulting in acute psychosis in a postoperative patient. Quetiapine is a cytochrome P40 3A4 substrate and phenytoin is a 3A4 inducer.


Pharmacokinetic Quetiapine CYP3A4 Phenytoin Induction Inducer Cytochrome P450. CYP 3A4 


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Melisa N. Weingarten
    • 1
  • Juraj Sprung
    • 2
  • Toby N. Weingarten
    • 2
  1. 1.Patient EducationMayo ClinicRochesterUSA
  2. 2.Department of AnesthesiologyMayo ClinicRochesterUSA

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