Patient Medicine Information
Why do I need this medicine?
Zafirlukast is used in the prevention and long-term treatment of asthma in adults and children 5 years and older.
How do I take this medicine?
Take Zafirlukast exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by the doctor.

Take Zafirlukast on an empty stomach, at least 1 hour before or 2 hours after a meal. Try to take it at the same time each day.

Zafirlukast must be taken regularly for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed by your doctor. Your condition may worsen if the medicine is stopped suddenly.
What should I do if I have forgotten to take this medicine?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.

DO NOT double a dose under any circumstances.

Remember to take your medicine regularly. If you often forget to take your medicine, let your doctor and pharmacist know.
When should I not use this medicine?
Alert you doctor if you have a history of liver disease as Zafirlukast may not be suitable for you.

Do not breastfeed while you are being treated with Zafirlukast.

Do not give Zafirlukast to children unless instructed by the child's doctor. Zafirlukast is not recommended for children 5 years old or younger.
What should I take note of while taking this medicine?
Let your doctor know if you are pregnant, think you are pregnant, or planning to have a baby soon.

Zafirlukast will not relieve sudden (acute) asthma attacks. Your doctor will provide you other medicines for sudden attacks.

Keep your appointments with your doctor. Your doctor may need to do routine blood tests to make sure that your liver function is normal.
What side effects could I experience?
Zafirlukast may make you drowsy or dizzy. If affected, do not drive or take part in any activity in which you need to be alert.

Other side effects include any of the following: headache, nausea, vomiting, diarrhea, stomach pain, rash, muscle pain, back pain, and weakness.

Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Inform your doctor and pharmacist if you are taking any of these medicines:

- medicines for blood clot e.g. warfarin, aspirin
- medicines for fungal infections e.g. fluconazole
- antibiotics e.g. erythromycin
- medicines for allergy e.g. terfenadine
- other medicines for asthma e.g. theophylline
- medicines for epilepsy (fits or seizures) e.g. carbamazepine, phenytoin

This list does not include all medicines that may interact with Zafirlukast.

Always notify your doctor or pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicine, supplements and medicines that you buy without a prescription.
What special dietary instructions should I follow?
Avoid alcohol.
How should I store this medicine?
Store in a cool, dry place away from the reach of children.

Medicines must not be used past the expiry date.
This information is independently developed by MIMS based on zafirlukast-oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2021 MIMS. All rights reserved. Powered by
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