Experiences with
MontelukastWho can take montelukast
Most adults and children aged 6 months old and over can take montelukast.
Who may not be able to take montelukast
Montelukast is not suitable for some people. To make sure it's safe for you, tell your doctor if you:
- have ever had an allergic reaction to montelukast or any other medicine
- have a rare hereditary problem of galactose intolerance (including Lapp lactase deficiency or glucose-galactose malabsorption)
Dosage
Montelukast comes as 10mg non-chewable tablets, chewable tablets in strengths of 5mg or 4mg, and granules in sachets of 4mg.
The usual dose for adults and children aged 15 years old and over is one 10mg tablet once a day.
The usual dose for children aged 6 to 14 years old is one 5mg chewable tablet once a day.
The usual dose for children from 6 months to 5 years old is 4mg once a day. This can be taken as granules, or a chewable tablet for children over 2 years old.
How to take it
Most people take montelukast once a day in the evening to prevent symptoms of asthma or allergies. However, if exercise makes your asthma worse, your doctor might tell you to take montelukast 2 hours before you exercise.
Never take more than 1 dose a day.
How to take non-chewable tablets
You can take montelukast non-chewable tablets with or without food.
Swallow the tablets whole with water, juice or milk. Do not chew these tablets.
How to take chewable tablets
It's important to take chewable tablets at least 1 hour before food, or 2 hours after food. This is so the medicine is absorbed into your body properly.
Chewable tablets can be chewed or sucked. You or your child can have a drink of water or squash afterwards.
How to give granules to a child
Montelukast granules come in a sachet with 4mg of granules inside (one dose). You can put them directly on your child's tongue. You can also mix the granules with a spoonful of cold, soft food, such as yoghurt or ice-cream.
Make sure your child takes the whole dose immediately (or within 15 minutes).
It's important not to dissolve the granules in a drink. You can give your child a drink afterwards.
How long to take it for
Take montelukast for as long as your doctor recommends it. It will only keep working while you're taking it.
Do not stop taking montelukast without speaking to your doctor first, because your symptoms may get worse.
If you forget to take it
If you or your child miss a dose of montelukast, skip the missed dose and take your next dose the following day at the usual time.
Do not take 2 doses to make up for a forgotten one.
If you forget doses often, it may help to set an alarm to remind you. You could also ask a pharmacist for advice on other ways to help you remember to take your medicine.
If you take too much
- you take more than your prescribed dose of montelukast
Get help from 111 online or call 111. Call 111 if you need advice for a child under 5 years old
If you need to go to A&E, do not drive. Ask someone to drive you or call 999 and ask for an ambulance.
Bring the montelukast packet or leaflet inside it, any remaining medicine, and any other medicines you take.
Common side effects
These common side effects of montelukast happen in more than 1 in 100 people. There are things you can do to help cope with them:
Drink lots of fluids, such as water or squash, to avoid dehydration. Signs of dehydration include peeing less than usual or having dark strong-smelling pee. Do not take any other medicines to treat diarrhoea without speaking to a pharmacist or doctor.
If you take the combined pill or progestogen-only pill and you have severe diarrhoea for more than 24 hours, your contraception may not protect you from pregnancy. Check the pill packet for advice.
Paracetamol will help to bring the temperature down. Drink plenty of fluids. See your doctor if it lasts for more than a few days.
Make sure you rest and drink plenty of fluids. Do not drink too much alcohol. Ask your pharmacist to recommend a painkiller.
Headaches should usually go away after the first week of taking montelukast. Talk to your doctor if headaches last longer than a week or are severe.
Try to rest and relax. It can help to eat and drink slowly and have smaller and more frequent meals. Putting a heat pad or covered hot water bottle on your stomach may also help.
If you're in a lot of pain, speak to your pharmacist or doctor.
Stick to simple meals and do not eat rich or spicy food. If you're being sick, try small frequent sips of water to avoid dehydration. Signs of dehydration include peeing less than usual or having dark strong-smelling pee.
If you take the combined pill or progestogen-only pill and you're being sick your contraception may not protect you from pregnancy. Check the pill packet for advice.
It may help to take an antihistamine, which you can buy from a pharmacy. Check with the pharmacist to see what type is right for you.
If the rash gets worse, speak to your doctor.
Speak to a doctor or pharmacist if the advice on how to cope does not help and a side effect is still bothering you or does not go away.
Serious side effects
Call your doctor or call 111 immediately if:
- you notice mood changes and you become anxious, depressed or aggressive
- you see things which are not there (hallucinations)
- you're finding it harder than usual to concentrate or remember things
- you have new problems with your sleep, or sleep problems that get worse, such as nightmares, sleepwalking or difficulty sleeping
- your speech changes or you start stuttering
- you have shaking or trembling in any part of your body
- you have an unusual or fast heartbeat
- you develop a combination of symptoms such as a flu-like illness, pins and needles or numbness of arms or legs, worsening of asthma symptoms, or a rash
- the whites of your eyes turn yellow, or your skin turns yellow although this may be less obvious on brown or black skin – this can be a sign of liver problems
It's important to tell your family or friends that you're taking montelukast, and that it may sometimes affect your mood, sleep or behaviour. This is so they can help you notice any changes.
- you have thoughts about harming yourself
It is possible to have a serious allergic reaction (anaphylaxis) to montelukast.
Meds New IA (H4) - serious allergic reactionThese are not all the side effects of montelukast. For a full list see the leaflet inside your medicines packet.
Montelukast and pregnancy
You can take montelukast during pregnancy. It's important that your asthma is well controlled. Having difficulty with breathing during pregnancy can be dangerous for you and your baby.
Speak to your doctor if you become pregnant while you're taking montelukast. They may wish to review your medicine to check that you're on the best treatment for your asthma.
Montelukast and breastfeeding
If your doctor, health visitor or midwife says your baby is healthy, you can take montelukast while you're breastfeeding.
It's important to continue taking montelukast to keep your symptoms under control. Breastfeeding will also benefit both you and your baby.
There is not much information about montelukast in breastfeeding, but the information shows that montelukast passes into breast milk in tiny amounts. It has not been known to cause any side effects in breastfed babies.
Talk to your health visitor, midwife, doctor or pharmacist as soon as possible if you have any concerns, including if your baby:
- is not feeding as well as usual
- seems unusually sleepy or irritable
- has diarrhoea
Montelukast and fertility
There's no evidence that montelukast affects fertility in either men or women.
Meds New IA (H2) - Pregnancy non-urgent care cardCautions with other medicines
There are some medicines that may affect how montelukast works.
Tell your doctor or pharmacist if you're taking any of these medicines:
- epilepsy medicines such as phenobarbital or phenytoin
- rifampicin, for tuberculosis and some other infections
- gemfibrozil, for high cholesterol
It's usually safe to take everyday painkillers with montelukast. However, do not take non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin or ibuprofen if they've ever made your asthma symptoms worse.
Mixing montelukast with herbal remedies and supplements
There's not enough information to say that complementary medicines and herbal remedies are safe to take with montelukast. They're not tested in the same way as pharmacy and prescription medicines. They're generally not tested for the effect they have on other medicines.
Meds New IA (H2) - Cautions with other medicines alertMontelukast is used to prevent the symptoms of asthma. It's usually prescribed when asthma is mild and can stop it from getting worse.
It can also help people with asthma who have breathing difficulties when they exercise (exercise-induced asthma) and seasonal allergies, such as sneezing, itchiness and a blocked or runny nose (allergic rhinitis).
Montelukast is sometimes given to people without asthma to treat hives (urticaria) that last for more than 6 weeks.
It's only available on prescription. It comes as tablets or granules.
Do not use montelukast to treat an asthma attack. Always use your reliever inhaler.
Related links
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