Itraconazole 100-200 mg was orally administered to 49 patients with pulmonary aspergilloma once a day in principle immediately after breakfast. Drug concentrations in fungus balls and in aspergilloma cavities were determined in each measurable case and the data were evaluated in terms of efficacy and safety. Overall evaluation was done considering the following 3 criteria: improvement of clinical symptoms, X-ray findings and mycological findings. The efficacy rate was 63.4% (26/41 cases). Out of 49 cases, adverse reactions and abnormal laboratory test values were observed in 8 (16.3%) and 13 (26.5%) cases, respectively. The safety rate was 81.6% (40/49 cases). 160 ng/g-4, 010 ng/g of itraconazole was detected in aspergilloma in 4 measurable cases. This finding showed that itraconazole had infiltrated into the fungus balls. Itraconazole was detected in aspergilloma cavities as well: drug concentration was 825 ng/g and 1,020 ng/g respectively. Based on overall view of clinical effects and drug concentrations in fungus balls and in the walls of lung cavities, it is concluded that itraconazole showed efficacy in reducing the size of aspergilloma and that this drug is useful also in terms of safety.