What is Montelukast (Singulair) used for?

Montelukast Indications

Montelukast is FDA-approved for three primary indications: prophylaxis and chronic treatment of asthma (ages 12 months and older), prevention of exercise-induced bronchoconstriction (ages 15 years and older), and relief of allergic rhinitis symptoms—both seasonal (ages 2 years and older) and perennial (ages 6 months and older). 1

Primary FDA-Approved Uses

Asthma Management

• Montelukast serves as a long-term controller medication for persistent asthma, working through leukotriene receptor antagonism to reduce airway hyperresponsiveness and inflammatory cell activity 2
• The medication is less effective than inhaled corticosteroids (ICS) as monotherapy and should not be used as first-line treatment when ICS are appropriate 2
• Montelukast is NOT for acute asthma attacks or immediate symptom relief—patients must always carry rescue inhalers 1
• As adjunctive therapy with ICS, montelukast is not the preferred add-on agent compared to long-acting beta-agonists (LABAs) in patients 12 years and older 2

Exercise-Induced Bronchoconstriction

• Take at least 2 hours before exercise for prevention in patients 15 years and older 1
• Do not take additional doses within 24 hours if already on daily montelukast for asthma or allergic rhinitis 1
• Frequent use before exercise may mask poorly controlled persistent asthma 2

Allergic Rhinitis

• Montelukast is less effective than intranasal corticosteroids for allergic rhinitis and should not be first-line therapy 2, 3
• The medication shows similar efficacy to oral antihistamines like loratadine but inferior to nasal steroids 2
• Onset of action occurs by the second day of daily treatment, which is slower than antihistamines 2, 3
• Approved for seasonal allergic rhinitis in patients 2 years and older, and perennial allergic rhinitis in patients 6 months and older 1

Optimal Clinical Positioning

When Montelukast Is Particularly Valuable

Combined Upper and Lower Airway Disease:

• Montelukast is especially appropriate for patients with both asthma and allergic rhinitis, as it addresses both conditions simultaneously 2, 3
• Up to 40% of allergic rhinitis patients have coexisting asthma, making montelukast a rational choice for dual benefit 2
• In children with mild persistent asthma and coexisting allergic rhinitis, montelukast has been recommended for monotherapy 2

Alternative When Steroids Are Problematic:

• Particularly attractive when treating children whose parents are "steroid-phobic" or refuse inhaled/intranasal corticosteroids 2
• Provides an option for patients unresponsive to, non-compliant with, or who have contraindications to intranasal corticosteroids 2

Combination Therapy:

• Combining montelukast with a second-generation antihistamine is superior to either agent alone for allergic rhinitis 2
• This combination may provide better protection against seasonal decrease in lung function 2
• In asthmatics with allergic rhinitis, combining montelukast with budesonide (nasal steroid) plus zafirlukast was more effective for bronchial symptoms than combining nasal steroid with antihistamines 2

Administration Guidelines

Dosing Schedule

• Take once daily in the evening for asthma patients 1
• For allergic rhinitis, take once daily at the same time each day 1
• May be taken with or without food 1
• Continue daily even when asymptomatic for chronic control 1

Important Safety Considerations

• Does not suppress skin testing, unlike antihistamines, which is advantageous for allergy evaluation 2
• Well-tolerated with a safety profile similar to placebo in clinical trials 2
• Does not affect growth rate in children 1

Common Pitfalls to Avoid

• Never use montelukast for acute symptom relief—it is a controller medication only 1
• Do not prescribe as first-line monotherapy for allergic rhinitis—intranasal corticosteroids are superior 2, 3
• Avoid using as preferred add-on therapy to ICS in asthma—LABAs are preferred in patients 12 years and older 2
• Do not use for direct cough suppression—it only helps cough secondary to allergic inflammation 4
• Recognize that montelukast provides continuous control rather than acute relief, with onset by day 2 of treatment 3