Helps prevent and control asthma attacks, including attacks caused by exercise. Also treats seasonal (short-term) and perennial (long-term) allergies.
There may be other brand names for this medicine.
When This Medicine Should Not Be Used
You should not use this medicine if you have had an allergic reaction to montelukast.
How to Use This Medicine
Packet, Tablet, Chewable Tablet
- Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
- This medicine comes with patient instructions. Read and follow these instructions carefully. Ask your doctor or pharmacist if you have any questions.
- You may take this medicine with or without food. Take the medicine at the same time every evening unless your doctor tells you otherwise.
- Swallow the tablet whole. Do not break, crush, or chew it. The chewable tablet must be chewed before you swallow it.
- Do not open the packet of oral granules until you are ready to use it. You can give the oral granules to a child in one of three different ways. Choose the way that works best for your child:
- Put the oral granules directly on a spoon, then into the child's mouth.
- Mix the granules with baby formula or breast milk. The formula should be cold or room temperature, not heated. Do not mix the medicine with any other type of liquid drink.
- Mix the oral granules with applesauce, mashed carrots, rice, or ice cream. Do not mix the granules with any other type of soft food. Use the mixed medicine right away and do not save any mixed medicine to use later.
If a dose is missed:
- If you miss a dose or forget to use your medicine, use it as soon as you can. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up for a missed dose.
How to Store and Dispose of This Medicine
- Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
- Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
- Keep all medicine away from children and never share your medicine with anyone.
Drugs and Foods to Avoid
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
- Make sure your doctor knows if you are taking phenobarbital (Luminal®) or rifampin (Rifadin®, Rimactane®).
Warnings While Using This Medicine
- Make sure your doctor knows if you are pregnant or breastfeeding, or if you have liver disease or are allergic to aspirin.
- This medicine will not stop an asthma attack that has already started. Your doctor may prescribe another medicine for you to use in case of a sudden asthma attack.
- If you use any type of corticosteroid medicine to control your asthma, keep using it as ordered by your doctor. This includes corticosteroid medicines that are taken by mouth or inhaled (such as cortisone, prednisone, Azmacort®, Celestone®, Cortone®, Deltasone®, Flovent®, Prelone® Pediapred®, Vanceril®).
- If any of your asthma medicines do not seem to be working as well as usual, call your doctor right away. Do not change your doses or stop using your medicines without asking your doctor.
- This medicine may cause some people to be agitated, disoriented, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. Report any unusual thoughts or behaviors that trouble you or your child, especially if they are new or get worse quickly. Make sure the doctor knows if you or your child have trouble sleeping, get upset easily, or start to act reckless. Also tell the doctor if you or your child have sudden or strong feelings, such as feeling nervous, angry, restless, violent, or scared.
- This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.
- The chewable tablet contains phenylalanine. Tell your doctor if you or your child have PKU (phenylketonuria) before taking the chewable tablet.
Possible Side Effects While Using This Medicine
Call your doctor right away if you notice any of these side effects:
- Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
- Ear, eye, tooth, or skin infection.
- Fast, slow, pounding, or irregular heartbeat.
- Numbness or tingling in the hands, arms, legs, or feet.
- Restlessness, anxiety, feeling irritable, disoriented, mood or behavior changes, or thoughts of hurting yourself or others.
- Seizures or tremors.
- Sudden and severe stomach pain, nausea, vomiting, fever, and lightheadedness.
- Swelling in your hands, ankles, or feet.
- Unusual bleeding or bruising.
- Unusual dreams or trouble with sleeping.
- Worsening asthma symptoms.
- Yellowing of your skin or the whites of your eyes.
If you notice these less serious side effects, talk with your doctor:
- Cough, sore throat, or flu symptoms.
- Diarrhea or indigestion.
- Headache or dizziness.
- Mild skin rash.
- Runny or stuffy nose.