1 What is Singulair?

Generic: Montelukast

Singulair is a prescription medicine used in treatment and prevention of asthma. Doctors prescribe Singulair to decrease the number of asthma attacks and minimize the symptoms.

Singulair, however, is not intended to relieve an attack that already started.

Apart from asthma, Singulair is also used in prevention of exercise-induced bronchoconstriction (EIB). Singulair is also used to treat symptoms of allergic rhinitis such as runny nose, sneezing, wheezing, and itching.

Singulair can only be purchased with doctor's prescription. 

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2 What to Know Before Using

Like any other medications, using Singulair should be a decision you make with your doctor. The risks and benefits the medicine offer must be weighed. For this medicine, you and your doctor must consider the following:


If you have any unusual reaction to any medicine, including Singulair, be sure to tell your doctor about it. Additionally, disclose other types of allergies - foods, preservatives, animals, or dyes, if there are any. Read the package ingredients carefully and make sure you are not allergic to any of its ingredients.

Use on children

Appropriate studies are done and have not shown pediatric-specific problems limiting the usefulness of Singulair in children aged 1 year and older who have asthma, children aged 6 years and older with EIB, children aged 2 years and above with seasonal allergies, and children aged 6 months and above with perennial allergies. The safety and efficacy of Singulair below this age groups are not yet established.

Use on elderly

Most recent appropriate studies have not shown geriatric-specific problems that would hinder the effects of Singulair in the elderly.


Call your doctor first before using Singulair in pregnancy. Studies show that Singulair does not demonstrate evidence of harm to the fetus when given to pregnant patients.


Call your doctor first before breastfeeding when taking Singulair.

Drug Interactions

Make sure to inform your doctor about other drugs you are taking, including prescription and over-the-counter drugs, before taking Singulair to avoid drug interactions. When prescribing Singulair, call your doctor if you are taking the following medicines:

  • Clozapine
  • Dasabuvir
  • Pixantrone
  • Nilotinib
  • Gemfibrozil
  • Prednisone

Other medical problems

Having certain medical problems may have an effect on how you use this medicine. If you have an allergy to NSAIDs and aspirin, or if you have an existing or history of phenylketonuria, inform your doctor before taking this medicine.

3 Proper usage

Singulair is available in tablets, chewable tablets, and granules that you take by mouth. Follow your doctor’s orders when using Singulair. Do not take more or use it more often, unless your doctor tells you otherwise. Singulair is not used and will not stop an asthma attack once it has already started. 

In order for Singulair to work properly, it has to be taken at the same time each day, regardless if the condition gets better. Singulair may be taken with or without food. If you are using Singulair oral granules, do not open the packet unless you are ready to use it.

For children, Singulair granules may be dissolved in 5 ml of breast milk or baby formula; or mixed with a tablespoon of soft food like rice, ice cream, applesauce, or mashed carrots. Do not mix Singulair granules with any other liquid; only use breast milk or formula in dissolving the granules. Once the medicine is mixed, it should be taken within 15 minutes. Do not store mixed Singulair for future use.


Follow your doctor’s orders in taking the right dose of Singulair. The following information only states the average dosages of Singulair, and you must still stick to doctor's orders. 

For prevention and treatment of asthma in adults and teens aged 15 and older, the usual dose of Singulair tablet is 10 mg once a day to be taken in the evening. Children aged 6 to 14 years may take Singulair 5 mg chewable tablet once a day. Children younger than 2-5 years old may take Singulair 4 mg chewable tablet or granules. For infants 12 to 23 months, the usual dosage is one packet (4 mg) Singulair granules once a day. 

For babies younger than 1 year old, consult your doctor. 

If you missed a dose of Singulair, take the missed dose as soon as possible. In case it is almost time for the next dose, skip the missed one and follow your regular dosing schedule. Never take double doses of Singulair.

Keep the Singulair in an airtight container at normal room temperature. Keep Singulair away from direct light, heat, and moisture. Keep the medicine out of children’s reach.

4 Precautions to take

Continue to take Singulair even if you are feeling well. If you are unable to take Singulair or have missed several doses, call your doctor.

You must regularly be seen by your doctor when you are taking Singulair. Keep up with lab and clinic appointments.

While using Singulair, you still have to avoid situations or activities that trigger asthma attacks. You may have to avoid drugs that trigger attacks such as Aspirin, other non-steroidal anti-inflammatory drugs (NSAIDs), Celecoxib, Diclofenac, Indomethacin, and Meloxicam.  

5 Potential side effects

Singulair may cause side effects in some patients. Call the doctor ifyou experience the following side effects of Singulair:

  • Severe allergic reaction symptoms such as skin rash, hives, difficulty breathing, swelling of the lips, mouth, nose, or throat
  • Severe skin reaction symptoms (rare) such as fever, sore throat, swelling of the face or tongue, burning pain of the eyes or skin, the appearance of red or purple skin rash, blistering, and peeling of the skin.
  • Changes in mood or behavior
  • Swelling, warmth, or pain in the ear

Singular may cause minor side effects that are no hazardous to health:

  • Stomach discomfort
  • Diarrhea
  • Fever and flu-like symptoms
  • Cold-like symptoms such as stuffy or runny nose, sinus discomfort, cough, and sore throat
  • Headache
  • Loss of bladder control or bedwetting in children

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