Zanamivir
Relenza is an inhaled antiviral medication containing zanamivir that works by inhibiting the neuraminidase enzyme on the surface of influenza viruses, preventing the virus from spreading to healthy cells. It is primarily used for the treatment and prevention of influenza A and B strains in adults and children aged 5 years and older.
Relenza is an inhaled antiviral used to treat and prevent influenza (the flu) by stopping the virus from spreading in the body.
Key facts at a glance
- RxNorm
- 261633
- Generic
- Relenza
- Class
- brand-name
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- —
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Relenza is used to treat uncomplicated influenza A and B infections in patients 7 years and older who have had symptoms for no more than 2 days. It is also used for prevention (prophylaxis) of influenza A and B in adults and children 5 years and older.
Relenza is a neuraminidase inhibitor. It works by blocking the neuraminidase enzyme on the surface of the influenza virus, which is needed for the virus to release from infected cells and spread to other cells. This helps reduce the duration and severity of flu symptoms.
Relenza is an inhaled powder and should not be used by patients with asthma or COPD due to the risk of bronchospasm. It is not a substitute for annual flu vaccination. Effectiveness may vary based on circulating flu strains. Side effects may include headache, throat discomfort, and respiratory symptoms.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy