zanamivir at a glance
Medicine class
Neuraminidase inhibitor antiviral
Licensed uses
Treatment and prevention of influenza A and B in adults and children aged 5 years and over
Administration
Dry powder inhaled through the mouth using the supplied Diskhaler
Important ingredient
Contains lactose monohydrate containing milk protein
What is zanamivir used for?
The inhaled product is licensed when influenza is circulating. Use should reflect current public-health recommendations.
Treatment of symptomatic influenza A or B in adults and children aged 5 years and over.
Prevention of influenza A or B after household contact with a clinically diagnosed case in adults and children aged 5 years and over.
In exceptional circumstances, prevention during a community outbreak, assessed case by case.
How does zanamivir work?
Influenza viruses use neuraminidase to release newly formed virus particles from infected airway cells. Zanamivir inhibits this enzyme, limiting the release and spread of influenza A and B viruses in the respiratory tract.
zanamivir preparations and strengths
Inhaled preparation
Route: Inhaled
Strengths: 5 mg/dose
How to take zanamivir
Use zanamivir exactly as prescribed and follow the pack’s illustrated Diskhaler instructions. Ask a pharmacist or clinician for a demonstration if needed.
Inhale the powder through the mouth using only the supplied Diskhaler and Rotadisk.
Do not swallow the powder or prepare it as a liquid.
Do not use the inhalation powder in a nebuliser or mechanical ventilator.
Pierce each blister only immediately before inhalation.
If other inhaled treatments are due at the same time, use them before zanamivir.
Sit in a relaxed position and hold your breath only as long as is comfortable.
Wipe the mouthpiece after use and replace its cover.
zanamivir side effects
Common or expected effects
- Skin rash
Get urgent medical advice
- Sudden bronchospasm, breathlessness, or throat or chest tightness
- Severe allergic reaction, including facial or throat swelling, hives or collapse
- Severe blistering, target-like or peeling skin rash
- Fainting or marked light-headedness after inhalation
- Seizures, hallucinations, confusion, reduced responsiveness or abnormal behaviour; these can also occur with influenza itself
zanamivir in pregnancy
Influenza can cause more serious illness during pregnancy, so treatment should not be withheld solely because someone is pregnant. UK public-health guidance generally places inhaled zanamivir after oral oseltamivir for most pregnant patients. Pregnancy data are limited, so use requires an individual benefit–risk assessment.
zanamivir while breastfeeding
UK specialist guidance states that zanamivir can be used cautiously during breastfeeding when clinically indicated because maternal absorption after inhalation is low and infant exposure is expected to be minimal. This applies to full-term, healthy infants; monitor for vomiting or skin reactions and seek specialist advice for a premature or unwell infant.
zanamivir interactions
Clinically significant pharmacokinetic interactions are considered unlikely because zanamivir is not metabolised by cytochrome P450 enzymes and is eliminated unchanged by renal filtration.
Inhaled bronchodilators and other inhaled respiratory treatments
When administration coincides, use the other inhaled treatment before zanamivir and keep any prescribed reliever inhaler available.
Influenza vaccine
Zanamivir does not replace vaccination and has not been shown to impair the immune response to influenza vaccine.
Common questions about zanamivir
Answers are fully visible for fast scanning and source review.
What is zanamivir used for?
It treats influenza A and B and, in specified circumstances, helps prevent influenza after exposure or during an outbreak.
Is zanamivir an antibiotic?
No. It is an antiviral neuraminidase inhibitor and does not treat bacterial infections.
Can zanamivir be put in a nebuliser?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.