The respiratory function test and biochemical blood indices mucinous 3EG5 antigene and eosinophil cation protein showing the bronchi reactivity state are studied in patients with outpatient pneumonia. It is established that the pneumonia course is characterized by delay of normalization of velocity indices in relation to volume finally resulting in transformation of disorders of the mixed type into obstructive. The significant increase of the level of the eosinophil cation protein is highly informative and sensitive indicator of the increase of bronchi reactivity. More pronounced and prolonged increase of the level of mucinous antigenereflecting mucous hypersecretion, aggravation of bronchi drenage function and strengthening bronchical obstruction are characteristic for lingering course of pneumonia