Some people using Singulair have had new or worsening mental problems. Stop taking montelukast and call your doctor right away if you have any unusual changes in mood or behavior (such as anger, aggression, confusion, sleep problems, compulsive behaviors, hallucinations, or suicidal thoughts or actions).
Tell your doctor right away if you have signs of blood vessel inflammation: flu-like symptoms, severe sinus pain, a skin rash, numbness or a "pins and needles" feeling in your arms or legs.
Singulair will not work fast enough to treat an asthma attack that has already begun. Use only a fast-acting inhalation medicine to treat an asthma attack. Talk with your doctor if any of your asthma medications do not seem to work as well in treating or preventing attacks.
Call your doctor right away if you feel that Singulair is not working as well as usual, or if it makes your condition worse. If it seems like you need to use more of any of your medications in a 24-hour period, talk with your doctor.
If you already take Singulair to prevent asthma or allergy symptoms, do not use it for exercise-induced bronchoconstriction.
It may take up to several weeks before your symptoms improve. Keep using Singulair as directed and tell your doctor if your symptoms do not improve after several weeks of treatment.
Before taking this medicine
You should not use Singulair if you are allergic to montelukast.
To make sure Singulair is safe for you, tell your doctor if you have ever had:
mental illness or psychosis; or
asthma, or a history of severe allergic reaction (sneezing, runny or stuffy nose, wheezing, shortness of breath) after taking aspirin or another NSAID.
The chewable tablet may contain phenylalanine and could be harmful if you have phenylketonuria (PKU).
Tell your doctor if you are pregnant or breastfeeding.
Do not give Singulair to a child without a doctor's advice.
How should I take Singulair?
Take Singulair exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.
Singulair is usually taken once daily in the evening for prevention of asthma or allergy symptoms. For exercise-induced bronchoconstriction, take a single dose at least 2 hours before you exercise, and do not take another dose for at least 24 hours. Follow your doctor's instructions.
Singulair is not a rescue medicine for asthma or bronchospasm attacks. Use only fast-acting inhalation medicine for an attack. Seek medical attention if your breathing problems get worse quickly, or if you think your medications are not working as well.
Swallow the regular tablet whole, with a glass of water.
You must chew the Singulair chewable tablet before you swallow it.
The oral granules can be placed directly into the mouth and swallowed, or mixed with a spoonful of applesauce, mashed carrots, rice, or ice cream. Oral granules can also be mixed with 1 teaspoon of baby formula or breast milk. Do not use any other type of liquid for mixing the granules.
After opening or mixing the Singulair oral granules, you must use them within 15 minutes. Do not save an open packet or mixed medicine for later use.
It may take up to several weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve.
Use all asthma medications as directed. Your dose needs may change due to surgery, illness, stress, or a recent asthma attack. Do not change your dose or dosing schedule without your doctor's advice. Tell your doctor if any of your medicines seem to stop working.
If you also use an oral steroid medication, you should not stop using it suddenly. Follow your doctor's instructions about tapering your dose.
Store Singulair at room temperature away from moisture and heat. Do not open a packet of oral granules until you are ready to use the medicine.
