[Level of evidence for therapeutic drug monitoring of itraconazole]

Abstract

Itraconazole is a triazole antifungal agent that is active against Aspergillus, histoplasmosis, and rare fungal infections. Itraconazole exhibit marked variability in drug concentration as a result of inconsistent absorption, metabolism, or interaction with concomitant medications. Preclinical and clinical data have exhibited a relationship between serum concentrations and treatment efficacy or toxicity, thus therapeutic drug monitoring (TDM) of itraconazole is largely used to optimise therapy. The analysis of bibliographic data demonstrate that, even if the utility of itraconazole's TDM has not been proved by randomized controlled trial or pharmaco-economics studies, it could be useful for managing an absence of response or a drug-drug interactions, or interpreting an adverse effect. However, the interest of this monitoring was proved only in some populations of patients (neutropenics or AIDS patients) so its level of proof varies between levels "potentially useful" and "recommended".