Singulair contains the active ingredient montelukast sodium, which is a selective leukotriene receptor antagonist. It is formulated as a 10 mg film-coated tablet intended for oral administration. The tablet contains inactive ingredients such as croscarmellose sodium, lactose monohydrate, and magnesium stearate.

How should I use this medication?

Take this medication by mouth with water. Take it as directed on the prescription label at the same time every day. Chew or crush it completely before swallowing. Do not swallow tablets whole. You can take this medication with or without food. If it upsets your stomach, take it with food. Keep taking it unless your care team tells you to stop. A special MedGuide will be given to you by the pharmacist with each prescription and refill. Be sure to read this information carefully each time. Talk to your care team about the use of this medication in children. While it may be prescribed for children as young as 2 years for selected conditions, precautions do apply.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once. NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, skip it. Take your next dose at the normal time. Do not take extra or 2 doses at the same time to make up for the missed dose.

Where should I keep my medication?

Keep out of the reach of children and pets. Store between 15 and 30 degrees C (59 and 86 degrees F). Protect from light and moisture. Keep the container tightly closed. Get rid of any unused medication after the expiration date. To get rid of medications that are no longer needed or expired: -Take the medication to a medication take-back program. Check with your pharmacy or law enforcement to find a location. -If you cannot return the medication, check the label or package insert to see if the medication should be thrown out in the garbage or flushed down the toilet. If you are not sure, ask your care team. If it is safe to put in the trash, empty the medication out of the container. Mix the medication with cat litter, dirt, coffee grounds, or other unwanted substance. Seal the mixture in a bag or container. Put it in the trash.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible: -Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat -Flu-like symptoms—fever, chills, muscle pain, cough, headache, fatigue -Mood and behavior changes such as anxiety, nervousness, confusion, hallucinations, irritability, hostility, thoughts of suicide or self-harm, worsening mood, feelings of depression -Pain, tingling, or numbness in the hands or feet -Sinus pain or pressure around the face or forehead -Trouble sleeping -Vivid dreams or nightmares Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome): -Cough -Diarrhea -Headache -Runny or stuffy nose -Sore throat -Stomach pain

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions: -Liver disease -Phenylketonuria -An unusual or allergic reaction to montelukast, other medications, foods, dyes, or preservatives -Pregnant or trying to get pregnant -Breastfeeding

What may interact with this medication?

-Medications for seizures, such as carbamazepine, phenytoin, phenobarbital -Rifabutin -Rifampin

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Visit your care team for regular checks on your progress. Tell your care team if your allergy or asthma symptoms do not improve. Take your medication even when you do not have symptoms. If you have asthma, talk to your care team about what to do in an acute asthma attack. Always have your inhaled rescue medication for asthma attacks with you. This medication may cause thoughts of suicide or depression. This includes sudden changes in mood, behaviors, or thoughts. Also watch for sudden changes in feelings and behaviors, such as feeling anxious, agitated, panicky, irritable, hostile, aggressive, impulsive, severely restless, overly excited and hyperactive, or not being able to sleep. Call your care team right away if you experience these behaviors or worsening depression.

What are the most serious risks of this medication?

This medicine can cause serious mental health problems. Patients of all ages and their families should watch for changes, especially sudden changes in mood, behaviors, thoughts, or feelings. Some symptoms to watch for are depression, thoughts of suicide, aggressive behavior, wanting to hurt others, hostility, anger, anxiety, irritability, being suspicious or distrustful, or any unusual or extreme changes in behavior or mood. Call your healthcare provider right away for new or worsening mental problems. Call your healthcare provider as needed, especially if you are worried about symptoms.