Voriconazole is used in adults and children 2 years of age and older to treat serious fungal infections such as invasive aspergillosis (a fungal infection that begins in the lungs and spreads through the bloodstream to other organs), esophageal candidiasis (a yeast [a type of fungus] infection that may cause white patching in the mouth and throat), and candidemia (a fungal infection in the blood). It is also used to treat certain other fungal infections when other medications will not work for certain patients. Voriconazole is in a class of antifungal medications called triazoles.