Abstract: The prevalence of comorbidity disease among patients of different ages is quite high and tends to increase . The presence of several diseases in the one patient at the same time affects each of them for their weights, promotes earlier formation creates complications and difficulties for the therapy. Particularly noteworthy is the combination of diseases that share common or similar etiological and pathogenetic factors. One of the most common types of comorbidity is a combination of asthma and obesity. Modern research has found a direct link between the increase in the incidence of asthma with increasing body mass index, and in patients with bronchial asthma incidence of overweight and obesity is twice higher than in the average. The current of asthma in overweight patients is more severe and it is difficult to control. Excess weight has a negative effect on the function of the respiratory system. In the analysis of the basic pathogenetic link of these comorbidities identified violations of immune system, there is an imbalance of production of proinflammatory and antiinflammatory cytokines – interleukins, recorded development of oxidative stress, there is disruption of nitric oxide production and activation of one of the types of eicosanoids – leukotrienes . Thus, as shown by the results of studies, asthma and obesity, are diseases in the body – forming sustained inflammation. Currently described and formulated many mechanisms by which obesity on asthma, but the approaches to the treatment of this comorbidity condition developed only taking into account some of the pathogenesis. Many components of the pathogenesis of this combined states remain unexplored and possible correction – unexplored.

Abstract: The important mediators of inflammation in bronchial asthma (BA) are leukotrienes (LT), which provide prolonged bronchoconstriction, secretion of viscous slime, neutrophil inflow, plasma exudation, and participate in immune reactions. LTS4, LTD4, LTE4 are called cysteine  LT, differ from LTB4 by the presence of a peptide group. Anti-leukotriene drugs have been developed against cysteine LT, the most commonly used of which is montelukast sodium. The aim of the study was to study the concentration of LTB4 in serum and urine of severe asthma patients.When studying the level of LTB4 in patients with asthma severe persistent, it was revealed that during the exacerbation the concentration of LTB4 was 16.7 times (p <0.001) higher than normal. Against the background of the basal therapy, which included montelukast sodium, when exiting from the exacerbation, the level of LTB4 was reduced, but its index remained 12.3 times (p <0.001) higher than in healthy ones. At the same time, the values of LTB4 in patients who did not receive montelukast did not differ significantly from those in the patients to whom it was assigned, which confirms the insufficient effectiveness of montelukast for this type of radiation therapy, which determines the directions for finding ways to improve the effectiveness of treatment.