Pulmonary hypersensitivity to nalfon.

Bilateral pulmonary infiltrates developed in a 77-year-old woman. These were associated with chills, fatigue, a high spiking temperature, leukocytosis, and eosinophilia. Clinical symptoms abated after 24 hours, and radiologic abnormalities cleared several days after discontinuing Nalfon, plus administering prednisone. The most likely cause of these pulmonary infiltrates was a hypersensitivity or idiosyncratic reaction to Nalfon.