Drug-associated interstitial lung disease: a diagnostic challenge

Drugs are frequently incriminated as the cause of interstitial pneumonia. There are two major mechanisms of drug-associated interstitial lung disease: direct toxicity and immunoallergic reaction. When a drug is suspected, the difficulty lies in obtaining proof. The chronology of the disease and its manifestations together with earlier evidence reported in the literature can lead to a tentative diagnosis of drug-associated interstitial pneumonia. Proof is obtained through surveillance during the disease course. In nearly all patients, therapeutic decisions must be taken on the basis of suspected drug involvement.