Montelukast at a glance
Medicine class
Leukotriene receptor antagonist.
Main role
Asthma control, including exercise-triggered airway narrowing; selected products also cover allergic rhinitis in people treated for asthma.
Asthma attacks
It does not relieve an acute asthma attack. Keep the prescribed reliever medicine available.
Available forms
Film-coated tablets, chewable tablets and granules. Administration and food instructions differ.
What is Montelukast used for?
Licensed uses vary by product, formulation and age group.
Add-on treatment for mild-to-moderate persistent asthma that remains inadequately controlled with inhaled corticosteroids and reliever treatment.
An alternative to inhaled corticosteroids in selected children who cannot use them and have no recent history of serious attacks requiring oral corticosteroids.
Prevention of asthma where exercise-induced bronchoconstriction is the predominant feature.
Relief of seasonal allergic rhinitis symptoms in eligible people for whom montelukast is already indicated for asthma; this use is product-specific.
How does Montelukast work?
Leukotrienes are inflammatory signalling chemicals that tighten and swell the airways. Montelukast blocks cysteinyl-leukotriene type 1 receptors, reducing bronchoconstriction and inflammation.
Montelukast preparations and strengths
Chewable tablet
Route: Oral
Strengths: 4 mg, 5 mg
Granules
Route: Oral
Strengths: 4 mg
Sachet
Route: Oral
Strengths: 4 mg
How to take Montelukast
Follow the prescription label and leaflet for the supplied formulation. Continue prescribed inhalers and keep the reliever inhaler available.
Swallow film-coated tablets whole; they may be taken with or without food.
Chew or suck chewable tablets before swallowing and follow their food-separation instructions.
Give granules directly into the mouth or mix with a small spoonful of cold, soft food. Use the complete mixture promptly, do not store it and do not dissolve granules in a drink.
Do not take another product containing montelukast at the same time unless specifically instructed.
Montelukast side effects
Common or expected effects
- Headache
- Stomach pain
- Diarrhoea
- Feeling or being sick
- High temperature
- Mild rash
Get urgent medical advice
- New or worsening mood, behaviour or sleep changes, including aggression, anxiety, depression, nightmares or hallucinations
- Suicidal thoughts or behaviour
- Severe allergic reaction
- Flu-like illness with rash, worsening breathing, numbness or pins and needles
- Yellow skin or eyes, which may indicate liver injury
Montelukast in pregnancy
Montelukast can be used during pregnancy when prescribed. Good asthma control is important, and available information does not raise concern about harm to the baby. Do not change asthma medicines without advice.
Montelukast while breastfeeding
Montelukast can generally be used while breastfeeding a healthy baby when recommended by a healthcare professional. Only tiny amounts are expected in milk; seek advice if the baby feeds poorly or develops unusual sleepiness, irritability or diarrhoea.
Montelukast interactions
Tell the prescriber or pharmacist about all medicines and supplements.
Phenytoin, phenobarbital and rifampicin
These can reduce montelukast exposure and potentially reduce its effect; particular caution is advised in children.
Gemfibrozil
It can substantially increase montelukast exposure, potentially increasing adverse reactions.
Aspirin and other NSAIDs in aspirin-sensitive asthma
Montelukast does not remove this sensitivity. Continue avoiding medicines known to worsen asthma.
Common questions about Montelukast
Answers are fully visible for fast scanning and source review.
Is montelukast sodium a steroid?
No. It is a leukotriene receptor antagonist, not a corticosteroid.
Can montelukast stop an asthma attack?
No. It does not replace the prescribed reliever inhaler during an acute attack.
Does montelukast replace my preventer inhaler?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.