Singulair (Montelukast) Dosing and Side Effects in 13-Year-Olds
For a 13-year-old with asthma, the recommended dose of Singulair (montelukast) is one 5-mg chewable tablet taken once daily in the evening, and the medication is generally well tolerated with a side effect profile similar to placebo. 1
Recommended Dosage
Standard Dosing:
- Children 6 to 14 years of age: 5 mg chewable tablet once daily in the evening 1
- The medication should be taken every day for as long as prescribed, even when asymptomatic 1
- Can be taken with or without food 1
For Exercise-Induced Asthma:
- If the 13-year-old is taking montelukast for exercise-induced bronchoconstriction specifically, the 5-mg dose should be taken at least 2 hours before exercise 1
- Critical pitfall: Do not take an additional dose if already taking daily montelukast for chronic asthma—the once-daily dose provides coverage for both conditions 1
For Allergic Rhinitis:
- Same 5-mg dose once daily at approximately the same time each day 1
Side Effect Profile
General Tolerability:
- Side effects are usually mild and generally do not cause discontinuation of therapy 1
- The frequency of adverse events in montelukast-treated children is comparable to placebo 2
- Clinical trials in children aged 2-14 years demonstrated that adverse events occurred at similar rates between montelukast and placebo groups 3
Common Side Effects to Monitor:
- Increased bleeding tendency 1
- Allergic reactions including facial/lip/tongue/throat swelling, hives, and itching 1
- Drowsiness, pins and needles/numbness 1
- Palpitations 1
- Nosebleed 1
- Gastrointestinal symptoms: diarrhea, indigestion, nausea, vomiting 1
- Joint pain, muscle aches and cramps 1
Serious Neuropsychiatric Side Effects (FDA Warning):
- Agitation including aggressive behavior or hostility 1
- Depression and suicidal thoughts/actions (including completed suicide) 1
- Anxiety, bad/vivid dreams, hallucinations 1
- Irritability, restlessness, sleep walking 1
- Tremor, trouble sleeping 1
The prescriber must inform the patient and family to immediately report any behavior or mood-related changes while taking montelukast. 1
Clinical Efficacy Context
Therapeutic Benefits:
- Onset of action occurs within one hour, with clinical benefits evident within 1 day of starting therapy 4, 3
- Improves daytime asthma symptoms (cough, wheeze, trouble breathing, activity limitation) 3
- Reduces overnight symptoms and need for rescue beta-agonist 2, 3
- Better patient satisfaction and compliance compared to inhaled therapies due to once-daily oral administration 4, 2
Treatment Position:
- Montelukast is an alternative treatment for mild persistent asthma when inhaled corticosteroids cannot be administered 4
- For moderate to severe persistent asthma, it is less efficacious than long-acting beta-agonists as add-on therapy to inhaled corticosteroids 4
- According to NAEPP guidelines, leukotriene receptor antagonists are appropriate alternative therapies for mild persistent asthma in patients unable or unwilling to use inhaled corticosteroids 5
Key Management Points
What to Avoid:
- Do not use montelukast for immediate relief of acute asthma attacks—always have an inhaled rescue medication available 1
- If asthma symptoms worsen or rescue inhaler use increases, contact the physician immediately 1
- Do not stop or reduce other asthma medications without physician instruction 1
- If asthma is aspirin-sensitive, continue avoiding aspirin and NSAIDs while taking montelukast 1
Monitoring Strategy:
- Watch for neuropsychiatric symptoms, particularly in the first weeks of therapy 1
- No routine laboratory monitoring is required—clinical trials showed no clinically meaningful differences in laboratory adverse effects between montelukast and placebo 3
- Assess asthma control regularly; if using short-acting beta-agonist more than 2 days per week for symptom relief, this indicates inadequate control and need to step up treatment 5