2 DOSAGE AND ADMINISTRATION Administration (by indications): Asthma ( 2.1 ): Once daily in the evening for patients 2 years and older. Acute prevention of EIB ( 2.2 ): 10 mg tablet at least 2 hours before exercise for patients 15 years of age and older. Seasonal allergic rhinitis ( 2.3 ): Once daily for patients 2 years and older. Perennial allergic rhinitis ( 2.3 ): Once daily for patients 2 years of age and older. Dosage (by age) 15 years and older: one 10 mg tablet 6 to 14 years: one 5 mg chewable tablet 2 to 5 years: one 4 mg chewable tablet Patients with both asthma and allergic rhinitis should take only one dose daily in the evening ( 2.4 ). 2.1 Asthma Montelukast sodium should be taken once daily in the evening. The following doses are recommended: For adults and adolescents 15 years of age and older: one 10 mg tablet. For pediatric patients 6 to 14 years of age: one 5 mg chewable tablet. For pediatric patients 2 to 5 years of age: one 4 mg chewable tablet Safety and effectiveness in pediatric patients less than 12 months of age with asthma have not been established. There have been no clinical trials in patients with asthma to evaluate the relative efficacy of morning versus evening dosing. The pharmacokinetics of montelukast are similar whether dosed in the morning or evening. Efficacy has been demonstrated for asthma when montelukast was administered in the evening without regard to time of food ingestion. 2.2 Exercise-Induced Bronchoconstriction (EIB) in Patients 15 Years of Age and Older For prevention of EIB, a single 10 mg dose of montelukast should be taken at least 2 hours before exercise. An additional dose of montelukast should not be taken within 24 hours of a previous dose. Patients already taking montelukast sodium daily for another indication (including chronic asthma) should not take an additional dose to prevent EIB. All patients should have available for rescue a short-acting β-agonist. Safety and effectiveness in patients younger than 15 years of age have not been established. Daily administration of montelukast sodium for the chronic treatment of asthma has not been established to prevent acute episodes of EIB. Pediatric use information for patients ages 6 to 14 years of age for acute prevention of exercise-induced bronchoconstriction (EIB) is approved for Merck Sharp & Dohme Corp’s montelukast tablet products. However, due to Merck Sharp & Dohme Corp’s marketing exclusivity rights, this drug product is not labeled with that pediatric information. 2.3 Allergic Rhinitis For allergic rhinitis, montelukast sodium should be taken once daily. Efficacy was demonstrated for seasonal allergic rhinitis when montelukast was administered in the morning or the evening without regard to time of food ingestion. The time of administration may be individualized to suit patient needs. The following doses for the treatment of symptoms of seasonal allergic rhinitis are recommended: For adults and adolescents 15 years of age and older: one 10 mg tablet. For pediatric patients 6 to 14 years of age: one 5 mg chewable tablet. For pediatric patients 2 to 5 years of age: one 4 mg chewable tablet Safety and effectiveness in pediatric patients younger than 2 years of age with seasonal allergic rhinitis have not been established. The following doses for the treatment of symptoms of perennial allergic rhinitis are recommended: For adults and adolescents 15 years of age and older: one 10 mg tablet. For pediatric patients 6 to 14 years of age: one 5 mg chewable tablet. For pediatric patients 2 to 5 years of age: one 4 mg chewable tablet Safety and effectiveness in pediatric patients younger than 6 months of age with perennial allergic rhinitis have not been established. 2.4 Asthma and Allergic Rhinitis Patients with both asthma and allergic rhinitis should take only one montelukast sodium dose daily in the evening.