Montelukast — NZ Medication Guide
📋 Reviewed by a Registered Pharmacist NZ — This information is for general educational purposes only and does not replace professional medical advice. Always consult your doctor or pharmacist before starting, stopping, or changing any medication.
What is Montelukast?
Montelukast is a leukotriene receptor antagonist used for asthma and allergic rhinitis. This medication is funded by Pharmac for asthma and allergic rhinitis.
What is Montelukast Used For?
Montelukast is used as add-on preventive therapy for mild-to-moderate persistent asthma, exercise-induced bronchoconstriction, and as an alternative or add-on to antihistamines for allergic rhinitis (hay fever), especially when accompanied by nasal congestion.
How Does Montelukast Work?
Montelukast selectively blocks cysteinyl leukotriene receptors (CysLT1 receptors) in the airways and nasal mucosa. Leukotrienes are inflammatory lipid mediators produced during allergic reactions that cause bronchoconstriction, airway inflammation, and mucus secretion. Blocking their receptors reduces these effects.
How to Take Montelukast
Taken once daily in the evening (evening dosing is preferred as leukotrienes are highest at night). Standard adult dose: 10 mg once daily. Chewable tablets (5 mg) are available for children aged 2–14 years.
Common Side Effects of Montelukast
- Headache
- Abdominal pain
- Nausea
- Fatigue
- Dizziness
- Rash
Serious Side Effects — Seek Medical Attention
Contact your doctor or call 111 immediately if you experience any of the following:
- Neuropsychiatric effects (Medsafe and FDA black box warning — reported cases of agitation, aggression, depression, hallucinations, sleep disturbances, suicidal ideation — monitor closely)
- Churg-Strauss syndrome (rare vasculitis — reported when oral corticosteroids are withdrawn in asthma patients on montelukast)
- Severe allergic reaction
Drug Interactions
Montelukast may interact with other medicines. Always inform your doctor and pharmacist of all medications you are taking. Key interactions include:
- Phenobarbital and rifampicin (reduce montelukast levels)
- CYP2C8 inhibitors (gemfibrozil — increase montelukast levels)
New Zealand Prescribing Information
Montelukast 10 mg tablets (Singulair® and generics) are funded by Pharmac. In 2020, Medsafe (and the FDA) strengthened warnings about neuropsychiatric side effects — prescribers must discuss these risks with patients and caregivers before starting. The benefits and risks should be weighed, particularly in patients with a history of depression or neuropsychiatric illness.
Frequently Asked Questions
Can montelukast cause mood or behaviour problems?
Yes — montelukast carries a Medsafe and FDA warning for neuropsychiatric effects including agitation, anxiety, depression, sleep disturbances, and suicidal thoughts (rare). If you notice any mood, behaviour, or sleep changes, contact your doctor promptly. The risks and benefits should be carefully discussed before starting.
Can I use montelukast instead of an inhaled steroid for asthma?
Montelukast is not a substitute for an inhaled corticosteroid (ICS) as a preventer in asthma. It is used as an add-on therapy or in patients with both asthma and allergic rhinitis. Your doctor will advise on the most appropriate asthma management plan.
⚠️ Disclaimer: This page is for educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your doctor or a qualified health provider. In New Zealand, medication availability and funding may vary — check with Pharmac or your pharmacist for current information.
Reviewed by a Registered Pharmacist NZ
References & Further Information
The following New Zealand and international resources were used to inform this page: