Asthma is a common heterogeneous disease, which often starts at a young age and has a reversible airway obstruction as its hallmark. Phenotypic differences in children with asthma may influence concomitant diseases and treatment choices. Despite the availability of effective drugs, asthma is poorly controlled in many children, which gives doctors the power to increasingly customize therapy from a personalized medicine perspective. The Global Initiative for Asthma (GINA) 2023 preserves and develops the agebased approach to diagnosis verification and therapy choice, which is supported in the All-Russia national program: Bronchial Asthma in Children and in the national clinical guidelines on bronchial asthma. Three age groups of patients were identified: zero to five years, six to eleven years and 12 years and older. Leukotriene receptor antagonists (in particular, montelukast) are often used in paediatric practice in children with asthma. The current guidelines show that leukotriene receptor antagonists (montelukast) are an alternative to inhaled glucocorticoids in mild, intermittent and persistent asthma. This is the first mediator-specific therapy for bronchial asthma. The best strategy in prescribing this group of drugs is to assess the severity of asthma, age and presence of concomitant diseases in children. The article uses clinical examples to discuss approaches to the asthma treatment with montelukast. The lack of asthma control tools results in high morbidity, mortality and costs of treatment, which justifies the search for new therapeutic options to improve control and reduce the risk of future exacerbations.