Gefitinib, an oral selective inhibitor of epidermal growth factor receptor tyrosine kinase, is a new molecular-targeted agent used for the treatment of patients with advanced non-small-cell lung cancer who fail to respond to traditional chemotherapy. Premarketing randomized double-blind phase 2 trials showed gefitinib to be relatively well tolerated, with mild adverse affects such as acneiform rash and diarrhea. After marketing, occasional pulmonary toxicity was identified, including occasionally fatal acute interstitial pneumonia. Some studies have noted severe alveolar hemorrhage in non-small-cell lung cancer patients treated with gefitinib.