Azoles

Pharmaceutical Applications

A large group of synthetic agents, which includes drugs used in bacterial and parasitic infections (5-nitroimidazoles; benzimidazoles). Antifungal azoles have in common an imidazole or triazole ring with N-carbon substitution. The activity is essentially fungistatic, but some of the newer triazoles exert fungicidal effects at therapeutic concentrations. They are effective in the topical treatment of dermatophytoses and superficial forms of candidosis; several are suitable for systemic administration.
Several molecular mechanisms of resistance have been elucidated. These include overexpression of efflux pump genes, point mutations in the gene that encodes the target enzyme, lanosterol demethylase, and overexpression of this gene. Changes in other enzymes involved in ergosterol biosynthesis, such as sterol desaturase, may also contribute to azole resistance.