Zafirlukast is used to prevent asthma attacks. It is not used to relieve an attack that has already started. For relief of an asthma attack that has already started, you should use an inhaled medicine that works quickly. If you do not have another medicine to use for an attack or if you have any questions about this, check with your doctor.
Use this medicine only as directed by your doctor. Do not use more of it and do not use it more often than your doctor ordered. Also, do not stop taking this medicine without telling your doctor. To do so may increase the chance of side effects.
This medicine usually comes with patient information leaflet. It is very important that you read and understand this information. Be sure to ask your doctor about anything you do not understand.
Food may change the amount of zafirlukast that is absorbed. It should be taken on an empty stomach, 1 hour before or 2 hours after a meal.
To work properly, zafirlukast must be taken every day at regularly spaced times, even if your asthma seems better.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage form (tablets):
- For asthma:
- Adults and children 12 years of age and older—20 milligrams (mg) two times a day.
- Children 5 to 11 years of age—10 mg two times a day.
- Children younger than 5 years of age—Use and dose must be determined by your doctor.
- For asthma:
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.