What montelukast is used for
Montelukast is a prescription medicine used to help control asthma and allergic rhinitis. Doctors may add it when inhalers alone do not fully control asthma, use it to prevent asthma triggered by exercise, or use it in children who find inhalers difficult. It can also ease sneezing and a blocked nose when allergies and asthma occur together.
In India, many people with asthma notice symptoms worsen with dust, smoke, cold mornings in winter and damp monsoon weather. Montelukast is a preventer, taken regularly as prescribed, not a medicine to use only when you feel breathless. Missing doses often leads to symptoms creeping back, so it helps to take it at the same time each day as your doctor directs.
- Long-term control of mild to moderate asthma, alongside inhalers
- Asthma triggered by exercise
- Allergic rhinitis, especially with asthma
- Children who have trouble using inhalers, on a doctor's advice
How montelukast works
When the airways meet a trigger, the body releases chemicals called leukotrienes. These cause the airway muscles to tighten, the lining to swell and extra mucus to form, leading to wheezing, cough and breathlessness. Montelukast blocks the receptors that leukotrienes act on, so the airways stay more open and calm.
Its effect builds up over days of regular use. It does not open the airways quickly during an attack, which is why a reliever inhaler, such as salbutamol, must always be kept at hand. Montelukast adds to the effect of other asthma medicines rather than replacing them, and your doctor will judge from your symptoms whether it is helping enough to continue.
Montelukast side effects: common and serious
Most people have no trouble with montelukast. Common side effects include headache, stomach pain, loose stools, and cold-like symptoms. Some people notice tiredness or mild skin rash. Children may have tummy aches or increased thirst. These effects are usually mild and often settle with time, but tell your doctor if they persist or bother you.
The most important warning is about mood and behaviour. Montelukast can occasionally cause nightmares, disturbed sleep, anxiety, irritability, aggression, depression and, rarely, suicidal thoughts in both children and adults. Rare serious effects also include severe allergic reactions and a condition with rash, numbness and worsening breathing. Report any such changes to your doctor promptly.
Who should take extra care with montelukast
People with a history of depression, anxiety or other mental health problems should discuss this with their doctor before starting montelukast. Parents should watch children for new sleep problems, bad dreams, bedwetting or changes in behaviour, and tell the doctor if they appear.
Montelukast is used in pregnancy and breastfeeding only when a doctor feels the benefit is worth it, so always tell your doctor if you are pregnant or planning pregnancy. People with liver disease need medical advice. Children should receive only the form and strength their doctor prescribes.
Montelukast interactions to know
Montelukast has few major interactions. Some epilepsy medicines such as phenytoin and carbamazepine, and the tuberculosis medicine rifampicin, may lower its levels in the blood and reduce its effect. Tell your doctor if you take any of these. Also mention any herbal or over-the-counter products, so your doctor has a complete picture of what you are taking.
Doctors often prescribe montelukast together with inhaled steroids or with an antihistamine such as levocetirizine when allergy is part of the problem. Combinations like these are a doctor's decision, based on how well your symptoms are controlled, and should not be started on your own.
Practical tips for using montelukast
Montelukast is only on a doctor's prescription. Take it regularly as prescribed, even on days when you feel well, and do not stop or change it on your own. Keep using your preventer inhaler if one has been prescribed; montelukast does not replace inhaled steroids for most people.
Always carry your reliever inhaler. Avoid known triggers such as smoke, incense, mosquito coils, dust and strong perfumes, and keep bedding clean and dry. Get your flu vaccine as your doctor advises. Visit your doctor regularly to review whether montelukast is still needed.
When to talk to your doctor about montelukast
See a doctor if you are using your reliever inhaler more often than usual, waking at night with cough or wheeze, or noticing any mood or sleep changes. Go to emergency care if breathlessness does not improve with your reliever. Ask your doctor or pharmacist if you have questions about your asthma medicines.
Related medicines
Only your doctor can decide which medicine, dose and combination is right for you.
- Inhaled corticosteroids such as budesonideThe main preventer medicine that calms airway inflammation in asthma.Only on a doctor's prescription; rinse your mouth after use.
- Salbutamol reliever inhalerQuickly opens tight airways during an asthma attack.Needing it often is a sign asthma is poorly controlled.
- Antihistamines such as levocetirizineEase sneezing, runny nose and itching from allergies.May cause drowsiness.
See a doctor urgently if
- Breathlessness that does not ease after using the reliever inhaler
- Lips or fingertips turning blue, or being too breathless to speak
- New thoughts of self-harm, severe low mood or aggressive behaviour
- Severe rash, swelling of the face or tingling and numbness in the limbs
- A child who becomes drowsy or struggles to breathe
Tests that may help
This article is general health information, not medical advice. Do not start, stop or combine medicines on your own — always follow your doctor's prescription and ask your pharmacist if unsure.