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Drug

Montelukast

Pronounced

"mon-teh-LEW-kast"

Uses

Montelukast is used to control and prevent symptoms caused by asthma (such as wheezing and shortness of breath). It is also used before exercise to prevent breathing problems during exercise (bronchospasm). This medication can help decrease the number of times you need to use your quick relief inhaler.

Montelukast is also used to relieve symptoms of hay fever and allergic rhinitis (such as sneezing, stuffy/runny/itchy nose). Since there are other allergy medications that may be safer (see also Warning section), this medication should be used for this condition only when you cannot take other allergy medications or they do not work well.

This medication must be used regularly to be effective. It does not work right away and should not be used to relieve sudden asthma attacks or breathing problems. If an asthma attack or sudden shortness of breath occurs, use your quick-relief inhaler as prescribed.

This drug works by blocking certain natural substances (leukotrienes) that may cause or worsen asthma and allergies. It helps make breathing easier by reducing swelling (inflammation) in the airways.

Warning

This medication may rarely cause serious mental/mood changes. These effects may occur even after the medication has been stopped. Tell your doctor right away if you or a caregiver/family member notice symptoms such as agitation, anxiety, abnormal dreams, depression, memory/attention problems, hallucinations, trouble sleeping, or changes in behavior (such as aggression, hostility, restlessness, sleepwalking, suicidal thoughts/attempts). Talk to your doctor about the risks and benefits of this medication.

How to Use This Medication

Read the Medication Guide provided by your pharmacist before you start taking montelukast and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor. The dosage is based on your age and medical condition.

You may swallow your dose plain, dissolve it in certain liquids, or mix it with a spoonful of soft food (such as applesauce) before swallowing. After opening the foil packet, take your dose within 15 minutes.

If you are mixing the granules in liquid, empty the packet into a small cup with 1 teaspoon (5 milliliters) of baby formula or breast milk (cool or at room temperature). Do not mix with water or other liquids. Stir well, and take the entire mixture right away. Do not save it for later use. After taking the liquid mixture, you may drink other liquids if desired.

If you are mixing the granules in soft food, mix only with the following foods: applesauce, mashed carrots, rice, or ice cream. Empty the packet into a small cup with 1 spoonful of soft food (cool or at room temperature) and mix completely. Take all of the mixture right away. Do not save it for later use.

Take this medication at the same time each day. If you are taking this medication for asthma or for both asthma and allergies, take your dose in the evening. If you are taking montelukast to prevent only allergies, take your dose either in the morning or the evening.

If you are taking this medication to prevent breathing problems during exercise, take your dose at least 2 hours before exercise. Do not take more than one dose in 24 hours. Do not take a dose before exercise if you are already taking this medication daily for asthma or allergies. Doing so may increase the risk of side effects.

Do not increase or decrease your dose or stop using this medication without consulting your doctor. Continue to use this medication regularly to keep your asthma under control, even during sudden asthma attacks or periods when you have no asthma symptoms. Continue to also take other medications for asthma as directed by your doctor.

This medication works over time and is not meant to relieve sudden attacks of asthma. If an asthma attack or other breathing problem occurs, use your quick-relief inhaler as prescribed. You should always have a quick-relief inhaler with you.

Learn which of your medications you should use every day and which you should use if your breathing suddenly worsens. Ask your doctor what to do if you have worsening cough or shortness of breath, wheezing, increased sputum, worsening peak flow meter readings, increased use of your quick-relief inhaler, or if your quick-relief inhaler does not seem to be working well. Learn when you can self-medicate and when you should get medical help right away.

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Drug information is selected from data included with permission and copyrighted by First DataBank, Inc. This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your healthcare professional. Always seek the advice of your healthcare professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your healthcare professional. This information does not contain any assurances that this product is safe, effective or appropriate for you.

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Information expires December 2025.