ICR mice were challenged with conidia of Aspergillus fumigatus given either intranasally or intravenously, and treated beginning 1 day later with itraconazole, amphotericin B, or the vehicles for these two agents. Mice challenged intravenously and treated with either antifungal drug had prolonged survival over controls, and had lower tissue counts in the kidneys than the controls. However, mice challenged intranasally had neither prolonged survival nor lower lung tissue counts than the controls.