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Fatal Forty DDI: diltiazem, carbamazepine, CYP3A4
  • Catherine Marcucci
  • Jerusha Taylor
  • Ansgar M. Brambrink
  • Neil B. Sandson


This case discusses a complex pharmacokinetic interaction between carbamazepine and diltiazem, resulting in carbamazepine toxicity and decreased efficacy of diltiazem. Carbamazepine is both a cytochrome P450 3A4 substrate and inducer and diltiazem is a 3A4 inhibitor and substrate.


Pharmacokinetic Inducer Inhibitor Induction Inhibition Carbamazepine Diltiazem CYP3A4 Paninducer Paninduction Toxicity Dizziness Ataxia Tremor Nystagmus Therapeutic drug monitoring Serum levels Cytochrome P450. CYP 3A4 


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Catherine Marcucci
    • 1
  • Jerusha Taylor
    • 2
  • Ansgar M. Brambrink
    • 3
  • Neil B. Sandson
    • 4
    • 5
  1. 1.Anesthesia Services DepartmentPhiladelphia Veterans Affairs Medical CenterPhiladelphiaUSA
  2. 2.Department of PharmacyOregon Health and Science UniversityPortlandUSA
  3. 3.Department of Anesthesiology and Perioperative MedicineOregon Health and Science UniversityPortlandUSA
  4. 4.Department of PsychiatryUniversity of Maryland Medical SystemBaltimoreUSA
  5. 5.Department of PsychiatryVA Maryland Health Care SystemBaltimoreUSA

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