Worsening pneumonitis due to a pharmacokinetic drug-drug interaction between everolimus and voriconazole in a renal transplant patient

Abstract

Orally administered voriconazole inhibits intestinal and hepatic cytochrome P450-3A4 activity and thereby reduces everolimus metabolism. An 80% decrease in dose or discontinuation of everolimus is required when concomitant voriconazole is introduced. Daily blood monitoring of everolimus is warranted until a steady state of concentrations is reached.