Montelukast sodium can treat pediatric allergic rhinitis with bronchial asthma. Clinically, both allergic rhinitis and bronchial asthma are airway sensitization diseases, which is also known as “same airway, same disease”. The typical manifestation of allergic rhinitis is triggered by the production of various inflammatory mediators after the body is exposed to allergens. Common allergic mediators include histamine and leukotrienes, among which leukotrienes are the main mediators in patients with allergic rhinitis and bronchial asthma. Montelukast sodium is a typical leukotriene antagonist, which can effectively block leukotriene receptor binding and thus achieve relief of allergy symptoms. Clinical treatment guidelines recommend that leukotriene antibody antagonists are preferred in children with allergic rhinitis combined with bronchial asthma.