Itraconazole has a broader spectrum of activity than fluconazole (but not as broad as voriconazole or posaconazole). In particular, it is active against Aspergillus, which fluconazole is not. It is also licensed for use in blastomycosis, histoplasmosis and onychomycosis. Itraconazole is over 99% protein bound and has virtually no penetration into cerebrospinal fluid. Therefore, it should never be used to treat meningitis or other central nervous system infections.^[1] According to the Johns Hopkins Abx Guide, it has "negligible CSF penetration, however treatment has been successful for cryptococcal and coccidioidal meningitis".^[2]

It is also prescribed for systemic infections such as aspergillosis, candidiasis and cryptococcosis where other antifungal drugs are inappropriate or ineffective. Itraconazole is currently being explored as an anti-cancer agent for patients with basal cell carcinoma, non-small cell lung cancer, and prostate cancer.^[3]