Montelukast 20mg Daily Dosing
No, you should not take montelukast 20mg in a day—the maximum approved dose is 10mg once daily for adults and adolescents 15 years and older. 1
FDA-Approved Dosing
The FDA-approved dosing for montelukast is specific and should not be exceeded 1:
- Adults and adolescents ≥15 years: 10mg once daily
- Children 6-14 years: 5mg once daily
- Children 2-5 years: 4mg once daily
- Children 12-23 months: 4mg once daily (oral granules)
All doses should be taken in the evening for asthma, or at the same time daily for allergic rhinitis. 1
Safety Data on Higher Doses
While clinical trials have evaluated doses up to 200mg daily (20 times the recommended dose) for up to 5 months in adults without dose-related adverse effects 2, this does not justify using supratherapeutic doses in clinical practice. Montelukast exhibits a flat dose-response curve, meaning doses greater than 10mg will not produce more efficacy than the standard dose. 3
Research specifically demonstrates that higher doses do not improve outcomes 3:
- In infants 6-24 months, doses >10mg showed no additional benefit over placebo
- The therapeutic effect plateaus at the recommended dose
Critical Safety Warning
The FDA issued a Black Box Warning for montelukast in March 2020 regarding neuropsychiatric events 3, including:
- Agitation and aggressive behavior
- Depression and suicidal thoughts/actions
- Hallucinations and sleep disturbances
- Anxiety and tremor 1
Taking double the recommended dose would increase exposure without additional benefit while potentially increasing the risk of these serious adverse effects.
Clinical Guidance
If asthma or allergic rhinitis symptoms are inadequately controlled on montelukast 10mg daily, the appropriate response is to step up therapy by adding or increasing inhaled corticosteroids, not increasing the montelukast dose. 3
The stepwise approach for inadequate control includes 3:
- Adding a long-acting beta-agonist to inhaled corticosteroids
- Increasing the dose of inhaled corticosteroids
- Considering alternative controller medications
- Consulting with an asthma specialist
Never exceed the FDA-approved dose of 10mg daily for adults. 1