Acute interstitial pneumonia induced by ONO-1078 (pranlukast), a leukotriene receptor antagonist.

A 62-year-old woman treated with pranlukast for 2 months developed interstitial pneumonitis with a high fever. A lymphocyte stimulation test was reactive to pranlukast. Her clinical symptoms improved with discontinuation of pranlukast and administration of systemic corticosteroid. To our knowledge, this is the first reported case of drug-induced lung disease involving a leukotriene. The steps that can be taken to promptly reach a diagnosis and to successfully treat this life-threatening condition are described.