When the Smoke Clears, Relaxation Disappears

Fatal Forty DDI: cyclobenzaprine, smoked tobacco, CYP1A2
  • Avinash Ramchandani
  • Julio A. Gonzalez-Sotomayor


This case discusses the pharmacokinetic interaction between cyclobenzaprine and smoked tobacco resulting in cyclobenzaprine toxicity due to reversal of enzyme induction. Cyclobenzaprine is a cytochrome P450 1A2 substrate. Smoked tobacco is a 1A2 inducer.


Pharmacokinetic Induction Inducer CYP1A2 Cytochrome P450 1A2 Tobacco Smoked tobacco Smoking Polycyclic aromatic hydrocarbons Cyclobenzaprine Flexeril 


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Avinash Ramchandani
    • 1
  • Julio A. Gonzalez-Sotomayor
    • 2
  1. 1.Pain Care PhysiciansAustinUSA
  2. 2.Pain Division, Department of Anesthesiology and Perioperative MedicineOregon Health and Science UniversityPortlandUSA

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