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Zanamivir

Sounds like 'za-nam-i-vir'. Also called Relenza.

Key points about zanamivir

Zanamivir is used to treat infection caused by the influenza (flu) virus.
Zanamivir is also called Relenza®.
Find out how to take it safely and possible side effects.

HN 0796 two pharmacists in discussion in dispensary of community pharmacy 950x690

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Zanamivir is used to treat and prevent symptoms caused by the influenza (flu) virus. It can make the symptoms of the flu less severe, help you recover faster and lower the chance of other problems occurring.

In Aotearoa New Zealand, zanamivir is available as a blister of powder (5 mg) to be inhaled using a special disk inhaler device. It’s available and funded for some people in hospital with a weakened immune system who are at higher risk of getting complications from the flu.

Zanamivir is available on a prescription from a prescriber but it’s not funded and you’ll need to pay the full cost.

To treat influenza

If you already have signs and symptoms of the flu, zanamivir helps to reduce symptoms such as fever, chills, stuffy nose, cough, sore throat, aches and tiredness. It shortens the time to recover from the flu by 12 to 24 hours.
Zanamivir is best started within an hour or two of the first symptoms of the flu, but it can still be effective after this time, as long as it's started within 48 hours of the first symptoms or within 36 hours for children.

To prevent influenza

If you’re at high risk of complications from getting the flu, you may be able to take zanamivir to help prevent it. For example, if you have come into contact with someone who already has the flu (such as a sick household member) or if there is a flu outbreak in the community.
To prevent influenza, it's best to start zanamivir within 36 hours of coming into contact with someone with the flu.
The best way to protect yourself against getting the flu is to get the flu vaccine every year. Zanamivir isn't a substitute for the flu vaccine.

The dose of zanamivir is different depending on whether it's used to treat influenza or prevent influenza.

To treat influenza: 2 inhalations, 2 times a day for 5 days.
To prevent influenza: 2 inhalations, once daily for 10 days. In some cases zanamivir can be continued for up to 28 days during an influenza epidemic.

Always take your zanamivir exactly as your healthcare provider has told you. The pharmacy label on your medicine will tell you how much zanamivir to take, how often to take it and any special instructions.

Zanamivir is a powder to be used with a special disk inhaler. The powder is in blisters in a foil disc to put into the disk inhaler. Your healthcare provider will show you how to use the disk inhaler. The following is a guide:

Remove the cover on your inhaler.
Check the inhaler to be sure it's clean.
Load the medicine foil into the inhaler.
Puncture 1 foil blister.
Keep the inhaler level so that the medicine doesn't spill out.
Breathe out all the way through your mouth, put the mouthpiece into your mouth and breathe in through your mouth as deeply as you can. This will draw the medicine into your lungs.
Hold your breath for a few seconds.
To take another dose, move to the next blister and repeat. Replace the cover of the inhaler to keep it clean.

If you are taking zanamivir 2 times a day, space your doses evenly, so take 1 dose in the morning and the other in the evening.

Missed dose: If you forget your dose, take it as soon as you remember that day. But if it's nearly time for your next dose, just take the next dose at the usual time. Don't take double the dose.
Keep taking zanamivir for the full time it has been prescribed: Stopping the medicine too early may cause a return of the infection or may not protect you from the flu.

Like all medicines, zanamivir can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Side effects	What should I do?
Itchy skin rash	This is common. Tell your doctor if this bothers you.
Feeling faint and lightheaded Dizziness	Sit down in a relaxed position before inhaling the dose of zanamivir, and only hold your breath for as long as is comfortable after inhaling the dose. Tell your doctor if these bother you.
Signs of an allergic reaction such as severe itchy skin rash (hives), swelling of your lips, face and mouth, or difficulty breathing	This is rare. Tell your doctor immediately or ring Healthline 0800 611 116.