Case report: delirium due to a diltiazem-fentanyl CYP3A4 drug interaction

Gen Hosp Psychiatry. 2010 Nov-Dec;32(6):648.e9-648.e10. doi: 10.1016/j.genhosppsych.2010.08.003. Epub 2010 Sep 22.

Abstract

Introduction: Fentanyl and diltiazem are frequently used medications. Diltiazem inhibits cytochrome P450 3A4 isoenzymes. This can suppress fentanyl metabolism.

Method: We present a case of delirium after coadministration of fentanyl and diltiazem.

Discussion: Cautious use is warranted while concomitantly administering fentanyl and diltiazem as this can potentiate fentanyl toxicity. Other 3A4 inhibitors include ketoconazole, erythromycin, nefazodone, ritonavir, delavirdine, aprepitant and imatinib. Psychosomatic medicine psychiatrists, pain and palliative care physicians and cardiologists in particular should be aware of this interaction.

Publication types

  • Case Reports

MeSH terms

  • Administration, Cutaneous
  • Aged, 80 and over
  • Analgesics, Opioid / adverse effects*
  • Analgesics, Opioid / pharmacokinetics
  • Analgesics, Opioid / therapeutic use
  • Calcium Channel Blockers / adverse effects*
  • Calcium Channel Blockers / therapeutic use
  • Cytochrome P-450 CYP3A
  • Cytochrome P-450 CYP3A Inhibitors*
  • Delirium / blood
  • Delirium / chemically induced*
  • Diltiazem / adverse effects*
  • Diltiazem / therapeutic use
  • Drug Interactions
  • Drug Therapy, Combination
  • Fentanyl / adverse effects*
  • Fentanyl / pharmacokinetics
  • Fentanyl / therapeutic use
  • Humans
  • Male
  • Oxycodone / adverse effects
  • Oxycodone / therapeutic use
  • Pain / drug therapy*
  • Tachycardia, Supraventricular / blood
  • Tachycardia, Supraventricular / drug therapy*

Substances

  • Analgesics, Opioid
  • Calcium Channel Blockers
  • Cytochrome P-450 CYP3A Inhibitors
  • Oxycodone
  • Cytochrome P-450 CYP3A
  • CYP3A4 protein, human
  • Diltiazem
  • Fentanyl