antibioticsbooks

Azoles
29
■■
Introduction to Azoles
Agents: ketoconazole, fluconazole,
itraconazole, voriconazole, posaconazole,
multiple topical formulations
The azoles are a broad class of antifungal agents
whose drug development has recently been expanding.
They work by inhibiting fungal cytochrome
P450, decreasing ergosterol production. One might
expect that this mechanism of action would lead to
issues with drug interactions, and this is indeed a
significant problem with these drugs. While most
drug interactions can be successfully dealt with by
dosage adjustment, this is not true for all of them.
Also, remember that any dose adjustments made
while a patient is receiving an interacting drug
need to be re-adjusted when the therapy with the
interactor is finished.
Azoles have become mainstays of antifungal
pharmacotherapy. As they have been developed,
agents of variable antifungal spectrums and toxicity
profiles have been introduced. These differences
are fundamental and are among the most important
characteristics to know if you use them clinically.
Because they are so different, we discuss the
commonly used systemic agents individually.