Abstract
A number of chemotherapeutic agents and multiple other drugs are known to produce interstitial pneumonitis and pulmonary fibrosis. It is important to realize which agents can produce or interact with other drugs to produce this complication. Two patients receiving combination chemotherapy with mitomycin‐C and vinblastine developed diffuse interstitial pulmonary infiltrates in temporal relationship to vinblastine administration. The infiltrates cleared but recurred and produced chronic pulmonary changes. Since it is likely that the vinblastine either caused or contributed to the pulmonary damage, this drug must be considered among the antineoplastic agents which can cause or contribute to interstitial pulmonary disease.