The article deals with the ethiopathogenetic characteristics, clinical manifestations, disease course, treatment and prevention of infectious disoders of the respiratory tract. Even in healthy people the course of acute respiratory viral infection (ARVI) may be complicated by the bacterial infection, but in the group of severe risk there are patients with comorbid background, especially the people with chronic pulmonary diseases (bronchial asthma, chronic obstructive pulmonary disease, etc.) and this condition is usually associated with the secondary immunodeficiencies. It is justified to use the immunotherapeutic drugs, for instance – inosine pranobex (Groprinosin®) as a prevention action or to increase the efficacy of antibacterial and antiviral therapy.

Cysteinyl leukotrienes which are products of lipoxygenase pathway of arachidonic acid metabolism play an important role in all phenotypes of bronchial asthma (BA). They are involved in immune and non-immune stimulation of different cells and inflammatory mechanisms in BA. Leukotrienes cause bronchoconstriction, increase vascular permeability and bronchial mucosa oedema, stimulate mucus secretion. Knowledge of leukotriene as inflammation mediators has allowed development leukotriene receptor antagonists and their implementation in clinical practice. Antiinflammatory properties of leukotriene receptor antagonists facilitate achievement asthma control while using both as monotherapy in mild asthma and in combinations with other antiasthmatic drugs in more severe disease. Currently, ongoing research of asthma phenotypes could define certain phenotypes with more important role of leukotrienes.

It is known that the bronchial asthma (BA) is a chronic inflammatory disease of the airways which involves many cells and cellular elements. Among various mediators involved in the pathogenesis of asthma cysteine leukotrienes (LT) are particularly relevant . The article details the questions of asthma therapy with the leukotriene receptor antagonist Montelukast drug, which based on the results of clinical trials is an effective anti-inflammatory drug, that allows to achieve controlled course of mild persistent BA within the framework of a monotherapy and in combination with inhaled corticosteroids - within the framework of a combined therapy. The medication demonstrates a special effectiveness in aspirin cold, allergic asthma and exercise-induced asthma, as well as the combination of asthma and allergic rhinitis.