A probable drug-to-drug interaction between voriconazole and haloperidol in a CYP2C19 poor metabolizing patient. [corrected]

Abstract

We present a case of Aspergillus fumigatus renal abscess treated with voriconazole. Following haloperidol treatment we observed an unexpected increase in voriconazole--trough concentrations and liver function tests. CYP2C19*2 loss of function allele was stated and the introduction of haloperidol, a weak CYP3A4 inhibitor, probably explains this interaction. [corrected]. Therapeutic drug monitoring and CYP2C19 genotyping may be suggested when administering voriconazole to complex patients.