Zafirlukast is used to prevent asthma symptoms. Zafirlukast is in a class of medications called leukotriene receptor antagonists (LTRAs). It works by blocking the action of certain natural substances that cause swelling and tightening of the airways.
Zafirlukast comes as a tablet to take by mouth. It is usually taken two times a day, 1 hour before or 2 hours after meals. Try to take zafirlukast at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take zafirlukast exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Do not use zafirlukast to treat a sudden attack of asthma symptoms. Your doctor will prescribe a short-acting inhaler to use during attacks. Talk to your doctor about how to treat symptoms of a sudden asthma attack.
Continue to take or use all other medications that your doctor has prescribed to treat your asthma. Do not stop taking any of your medications or change the doses of any of your medications unless your doctor tells you that you should.
Zafirlukast may help control asthma symptoms, but it does not cure asthma. Continue to take zafirlukast even if you feel well. Do not stop taking zafirlukast without talking to your doctor.
Zafirlukast is also sometimes used to treat allergic rhinitis (hay fever; runny nose, watery eyes, and other symptoms caused by an allergic reaction to pollen or other substances in the air). Zafirlukast is also sometimes used to prevent breathing difficulties during exercise in people who have asthma.
Unless your doctor tells you otherwise, continue your normal diet.
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
loss of appetite
pain in the right upper part of your stomach
lack of energy
yellowing of the skin or eyes
swelling of the eyes, face, lips, tongue, or throat
difficulty breathing or swallowing
pain, burning, numbness, or tingling in the hands or feet
Zafirlukast may cause other side effects. Call your doctor if you have any unusual problems while you are taking this medication.
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light, excess heat, and moisture (not in the bathroom) . Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your response to zafirlukast.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
Last Revised - 12/01/2009
AHFS® Consumer Medication Information. © Copyright, 2013. The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.