Zanamivir is used to prevent and treat influenza virus A and B infections.
Follow the dosing instructions carefully and remember to take the complete course.
You can help prevent the virus from spreading to others by using clean tissues to cover your mouth and nose when coughing and sneezing, carefully disposing of tissues after each use and washing your hands regularly.
Remember to keep warm, drink plenty of fluids and stay away from crowds.
About zanamivir
Type of medicine
Antiviral
Used for
Treating or preventing influenza (flu).
Also called
Relenza®
Available as
Diskhaler (for inhalation)
Zanamivir works by preventing influenza viruses A and B from spreading inside the body. By doing this it reduces or prevents the symptoms of the influenza virus infection. As well as relieving the symptoms of flu, it also shortens the time of illness by around one day and reduces the risk of other problems that can occur alongside flu, such as pneumonia.
It is most effective in reducing the symptoms of flu if it is started within a few hours of the first symptoms of the infection. It can however be started up to 48 hours after the start of the infection in adults and 36 hours in older children.
It is also used to prevent flu when there are high levels of influenza in the community such as in epidemics and pandemics. It is useful for those who have been in close contact with people suffering from influenza at these times, or those who would be at particular risk if they developed flu.
Zanamivir is not a substitute for seasonal flu vaccination.
Before taking zanamivir
Before taking zanamivir make sure your doctor or pharmacist knows:
If you are pregnant, trying for a baby or breast-feeding.
If you have breathing problems such as asthma.
If you are taking other medicines, including those available to buy without a prescription, herbal or complementary medicines.
If you have ever had an allergic reaction to this or any other medicine.
How to take zanamivir
Before beginning treatment, read the manufacturer's printed information leaflet which explains how to use the diskhaler.
Take zanamivir exactly as directed by your doctor.
Zanamivir is a course of treatment which usually lasts 5-10 days although it may sometimes be taken for up to 28 days. Remember to complete the whole course (even if you do not feel unwell), otherwise your symptoms may return.
Try to take zanamivir at the same time(s) each day to avoid missing any doses.
If you forget to take a dose, take one as soon as you remember unless it is time for your next dose. Do not take two doses at the same time to make up.
Getting the most from your treatment
If you are due doses of any other inhalers at the same time as zanamivir, take your dose of zanamivir after your usual inhaler. If you use a reliever inhaler (such as salbutamol) keep this with you in case you need to use it.
Can zanamivir cause problems?
It is unusual to experience any side-effects of treatment with zanamivir but should you experience any difficulties with breathing then it is important to let your doctor know as soon as possible.
If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.
How to store zanamivir
Keep all medicines out of the reach and sight of children.
Store in a cool, dry place, away from direct heat and light.
Important information about all medicines
If you are having any treatment like an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.
If you buy any medicines, check with a pharmacist that they are safe to take with your other medicines.
Never take more than the prescribed dose. If you suspect that you or someone else has taken an overdose of this medicine, go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.
This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
Never keep out of date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
If you have any questions about this medicine ask your pharmacist.
References
Manufacturer's PIL, Relenza®, GlaxoSmithKline UK, electronic Medicines Compendium. Dated October 2008, accessed May 2009.
British National Formulary; 57th Edition (March 2009) British Medical Association and Royal Pharmaceutical Society of Great Britain, London (link to current BNF).
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