A Hidden Drug

Fatal Forty DDI: diltiazem, sildenafil, CYP3A4 and sildenafil, nitroglycerin


This case discusses both a pharmacokinetic and a pharmacodynamic interaction between sildenafil and diltiazem. Sildenafil is a cytochrome P450 3A4 substrate. Diltiazem is a 3A4 inhibitor. In addition, the coadministration of sildenafil and diltiazem can result in severe hypotension.


Pharmacodynamics Pharmacokinetic CYP3A4 CYP 3A4 Cytochrome P450 Sildenafil Diltiazem Inhibitor Amoxicillin Clarithromycine Erythromycin Sodium nitrates Ketoconazole Lopinavir Ritonavir Angina Nitroglycerin Hypotension Phosphodiesterase type 5 Nitric oxide Cyclic guanosine monophosphate Cyclic GMP Nicorandil Nipradilol Corpus callosum 


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Helga Komen
    • 1
  • Toby N. Weingarten
    • 2
  • Juraj Sprung
    • 2
  1. 1.Department of Anesthesiology and Critical Care MedicineUniversity Hospital RijekaRijekaCroatia
  2. 2.Department of AnesthesiologyMayo ClinicRochesterUSA

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