How does montelukast work?
Montelukast blocks leukotrienes, chemicals in the body that cause inflammation, swelling, and mucus production. This helps keep the airways open and reduces asthma and allergy symptoms.
What is montelukast used to treat?
Montelukast is commonly prescribed for:
- Asthma prevention (to reduce symptoms and prevent attacks)
- Exercise-induced asthma (to prevent breathing difficulties during physical activity)
- Hay fever (allergic rhinitis) (to relieve sneezing and nasal congestion)
Who can take montelukast?
Montelukast is suitable for adults and children over 6 months old, depending on the condition being treated.
Who might not be able to take montelukast?
Montelukast may not be suitable if you:
- Have a history of severe allergic reactions to montelukast
- Have liver disease
- Experience mood changes or mental health issues while taking it
Can I take montelukast if I’m pregnant or breastfeeding?
Montelukast isn’t usually recommended during pregnancy or while breastfeeding unless advised by a doctor.
What if I miss a dose?
If you forget a dose, take it as soon as you remember. If it’s close to your next dose, skip the missed one—do not take two doses at once.
How effective is montelukast?
Montelukast is effective at reducing asthma and allergy symptoms when taken regularly. It does not provide immediate relief for asthma attacks—a reliever inhaler should be used instead.
What should I do if I take too much?
Taking too much montelukast may cause stomach pain, drowsiness, or mood changes. If you feel unwell, seek medical advice.
What dose of montelukast is usually taken?
- For asthma prevention (adults & children over 15): 10mg once daily in the evening
- For exercise-induced asthma: 10mg at least 2 hours before exercise
- For hay fever: 10mg once daily as needed during allergy season
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What are the side effects of montelukast?
Common side effects include:
- Headache
- Stomach pain or diarrhoea
- Sleep disturbances (such as vivid dreams or trouble sleeping)
- Mood changes (such as anxiety or irritability)
Serious side effects, such as suicidal thoughts or severe allergic reactions, require urgent medical attention.
How should I take montelukast?
Montelukast is taken as a tablet, chewable tablet, or granules (for young children). It should be swallowed whole with water.
When should montelukast be taken?
Montelukast is usually taken once daily in the evening, as this is when it works best for asthma control.
What are the brand names for montelukast?
Montelukast is available as a generic medicine, but some branded versions include:
- Singulair
Final thoughts
Montelukast is an effective treatment for asthma and allergies, but it should be taken regularly to prevent symptoms. If you experience side effects or worsening symptoms, speak to your doctor or pharmacist.
