Utilization of omeprazole to augment subtherapeutic voriconazole concentrations for treatment of Aspergillus infections.

Voriconazole is the preferred antifungal agent for Aspergillus infections. Therapeutic drug monitoring is recommended to achieve target concentrations and prevent toxicity. However, variable pharmacokinetics, cytochrome P450 polymorphisms, and extensive drug-drug interactions can contribute to subtherapeutic concentrations. We report a voriconazole "boosting" effect of omeprazole to achieve target concentrations for the treatment of Aspergillus in a patient who had persistently subtherapeutic trough concentrations.