Allergic rhinitis as one of the most common non-infectious respiratory inflammatory diseases is a global public health problem. The course of allergic rhinitis, its effect on the pathology of other organs and systems, the likelihood of complications and many other aspects of this pathology are largely determined by timely diagnosis and adequate treatment. At the heart of the pathogenesis of allergic rhinitis is the immediate allergic reaction. Histamine is the most important biogenic amine, the physiological regulator of the activity of various cells and systems and one of the main mediators of allergic reactions of immediate type. In the treatment of allergic rhinitis, one of the key places is occupied by antihistamines. One of such highly effective modern antihistamines is levocetirizine – a blocker of H1 histamine receptors of the second generation. Leveltzetirizine affects the histamine-dependent stage of allergic reactions, reduces vascular permeability and eosinophil migration, limits the release of inflammatory mediators, significantly influences the formation of edema of the tissues and the production of mucus, prevents development and greatly facilitates the course of the allergic reaction, has antiexudative, antipruritic and anti-inflammatory effects, and a pronounced ability to eliminate nasal obstruction in patients with seasonal allergic rhinitis. The drug levocetirizine Allerway®, bioequivalent to the original drug, is of definite interest to physicians of various specialties.