Montelukast sodium tablets are a leukotriene receptor antagonist indicated for: Prophylaxis and chronic treatment of asthma in patients 12 months of age and older. Acute prevention of exercise-induced bronchoconstriction (EIB) in patients 6 years of age and older. Relief of symptoms of allergic rhinitis (AR): seasonal allergic rhinitis (SAR) in patients 2 years of age and older, and perennial allergic rhinitis (PAR) in patients 6 months of age or older.