In this drug factsheet:
How does this medication work? What will it do for me?
Montelukast belongs to a group of medications known as leukotriene receptor antagonists. It is used to prevent and manage asthma symptoms and to relieve the symptoms of seasonal allergies, also known as seasonal allergic rhinitis or hay fever. It works by blocking the effects of leukotrienes, a substance produced by the body in response to certain "triggers" that cause narrowing and swelling of airways in the lungs. Montelukast usually starts to work within one day.
When used to prevent and manage asthma, it is important to understand that montelukast should not be used to relieve an asthma attack once it has started. People with asthma should always have their fast-acting asthma relief medication on hand to treat an asthma attack.
Your doctor may have suggested this medication for conditions other than the ones listed in these drug information articles. As well, some forms of this medication may not be used for all of the conditions discussed here. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.
Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.
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How should I use this medication?
For seasonal allergic rhinitis, the recommended dose of montelukast for adults and adolescents 15 years and older is one 10 mg tablet taken once a day in the evening.
For asthma, the recommended dose of montelukast for adults and adolescents 15 years and older is one 10 mg tablet taken once a day in the evening. For children 6 to 14 years old, the recommended dose is one chewable 5 mg tablet taken once a day in the evening. For children 2 to 5 years old, the recommended dose is one chewable 4 mg tablet or one packet of 4 mg granules taken in the evening.
Montelukast can be taken with or without food.
The oral granules can be given either directly in the mouth, or mixed with a spoonful of cold or room temperature soft food (e.g., apple sauce). The packet should not be opened until ready to use. After opening the packet, the full dose of oral granules must be given within 15 minutes. Do not store any oral granule and food mixture for later use. Do not mix the oral granules in liquid. Children may drink liquids after swallowing the oral granules.
Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.
It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.
Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.
Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.
What form(s) does this medication come in?
10 mg tablet
Each beige, rounded square-shaped, film-coated tablet, with the code "MSD 117" on one side and "SINGULAIR" on the other, contains montelukast sodium 10.4 mg, which is the molar equivalent of free acid 10 mg. Nonmedicinal ingredients: croscarmellose sodium, hydroxypropyl cellulose, lactose monohydrate, magnesium stearate, and microcrystalline cellulose; film-coating: carnauba wax, hydroxypropyl cellulose, hydroxypropyl methylcellulose, red ferric oxide, titanium dioxide, and yellow ferric oxide.
4 mg chewable tablet
Each pink, oval, biconvex-shaped, chewable tablet, with the code "MSD 711" on one side and "SINGULAIR" on the other, contains montelukast sodium 4.2 mg, which is the molar equivalent to free acid 4 mg. Nonmedicinal ingredients: aspartame, cherry flavor, croscarmellose sodium, hydroxypropyl cellulose, magnesium stearate, mannitol, microcrystalline cellulose, and red ferric oxide.
5 mg chewable tablet
Each pink, round, biconvex-shaped, chewable tablet, with the code "MSD 275" on one side and "SINGULAIR" on the other, contains montelukast sodium 5.2 mg, which is the molar equivalent to free acid 5 mg. Nonmedicinal ingredients: aspartame, cherry flavor, croscarmellose sodium, hydroxypropyl cellulose, magnesium stearate, mannitol, microcrystalline cellulose, and red ferric oxide.
4 mg granules
Each 4 mg packet of oral granules (presented as a white, coarse, granular, free-flowing homogeneous solid in a foil packet) contains montelukast sodium 4.2 mg, which is the molar equivalent to 4 mg of free acid. Nonmedicinal ingredients: hydroxypropyl cellulose, magnesium stearate, and mannitol.
Who should NOT take this medication?
Do not take this medication if you are allergic to montelukast or any ingredients of the medication.