About zafirlukast
Leukotriene receptor antagonist
Used for
- Long-term control and prevention of asthma symptoms
Usual adult dose
Adults and adolescents 12 years and older: 20 mg twice daily, taken away from meals.
Usual dose in children
Children 5–11 years: 10 mg twice daily, taken away from meals.
Common side effects
- Headache
- Nausea or diarrhea
- Abdominal pain
- Infections, such as colds
Important warnings
- Not for sudden asthma attacks; keep rescue treatment available.
- Rare serious liver injury has occurred.
- Do not stop or reduce inhaled steroids without medical guidance.
- Take at least one hour before or two hours after food.
Pregnancy
Use only when clearly needed; discuss potential benefits and risks with a healthcare professional.
Breastfeeding
Whether zafirlukast passes into breast milk is uncertain; discuss use with a healthcare professional.
Interactions
- Warfarin: increased anticoagulant effect and bleeding risk.
- Erythromycin may reduce zafirlukast levels.
- Theophylline may reduce zafirlukast levels.
- Aspirin may increase zafirlukast levels.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.