ABSTRACT
Oral administration of Qing-Fei-Tang improved symptoms of a patient suffering from acute bronchitis with severe cough and sputum. Chemiluminescence (CL) of oxygen radical stimulated by opsonized zymosan in the peripheral blood of the patient was abnormally high before administration of Qing-Fei-Tang. The elevated CL was normalized after 5 week-administration of the drug. <i>In vitro</i> study, Qing-Fei-Tang suppressed in a dose dependent manner the CL of oxygen radical generation in normal human leukocytes stimulated by opsonized zymosan, and also inhibited a release of slow reacting substance of anaphylaxis (SRS-A) from sensitized guinea pig lung tissues after antigen challenge. These results suggest the suppression by Qing-Fei-Tang of release of a chemical mediator, like SRS-leukotriene, may be involved in the improvement of symptoms of the acute bronchitis.