Despite recognition of acute respiratory distress syndrome in both falciparum and vivax malaria, disease-related changes in pulmonary function have not been defined, and underlying mechanisms are not well understood. Respiratory symptoms, pulmonary function, pulmonary phagocytic cell activity, and longitudinal changes were examined in 26 adults with uncomplicated falciparum, vivax, and ovale malaria after treatment. Self-limiting cough occurred in both falciparum (36%) and vivax or ovale (53%) malaria. In infection with each malaria species, admission measures of airflow and gas transfer were lower than predicted, and mean lung 99mtechnetium-sulfur-colloid uptake was significantly increased. Changes were most evident in falciparum malaria, with treatment resulting in initial worsening of airflow obstruction and gas transfer. Altered pulmonary function in malaria is common and includes airflow obstruction, impaired ventilation, impaired gas transfer, and increased pulmonary phagocytic activity, and its occurrence in both vivax and falciparum malaria suggests that there may be common underlying inflammatory mechanisms.