Zanamivir (zan-AM-e-veer) is used in the treatment of the infection caused by the flu virus (influenza A and influenza B). Zanamivir may reduce flu symptoms (weakness, headache, fever, cough, and sore throat) by 1 to 1.5 days. Zanamivir does not prevent influenza infection.

This medicine must be started within 2 days of having flu symptoms (weakness, headache, fever, cough, and sore throat). Zanamivir will not keep you from spreading the flu virus to other people. Zanamivir may not work for everybody. Zanamivir may not be for you if you are severely sick or have a breathing problem (like asthma or chronic obstructive pulmonary disease). If you receive the flu vaccine every year, continue to do so.

Allergies Tell your doctor if you have ever had any unusual or allergic reaction to zanamivir.

Pregnancy Zanamivir has not been studied in pregnant women. However, zanamivir has not been shown to cause birth defects or other problems in animal studies.

Breast-feeding It is not known whether zanamivir passes into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are using this medicine and who wish to breast-feed should discuss this with their doctor.

Children This medicine is not recommended for use in children younger than 7 years of age. This medicine has been tested in children 12 years and older and has not been shown to cause different side effects or problems in these children than it does in adults.This medicine is available in Canada. It is not recommended in children younger than 12 years of age.

Older adults This medicine has been tested in older adults and has not been shown to cause different side effects or problems in older adults than it does in younger adults.

Other medicines Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your health care professional if you are taking any other prescription or non-prescription (over the counter [OTC]) medicine before using zanamivir.

Other medical problems The presence of other medical problems may affect the use of zanamivir. Make sure to tell your doctor if you have any other medical problems, especially:

• Lung Disease Patients with lung disease (chronic obstructive pulmonary disease or asthma) may experience trouble breathing with the use of zanamivir. Zanamivir may not work in patients with chronic lung disease.

• Heart Disease Zanamivir may not work in patients with heart disease.

Talk to your doctor about the possibility of getting a flu shot if you have not had one yet. This medicine works best if taken as soon as possible after exposure to people who have the flu. If you already have the flu, continue taking this medicine for the full time of treatment even if you begin to feel better after a few days. This will help to clear up your infection completely. If you stop taking this medicine too soon, your symptoms may return. This medicine should be taken for 5 days.

Inhaled zanamivir is used with a special inhaler and usually comes with patient directions. Read the directions carefully before using this medicine. If you do not understand the directions or you are not sure how to use the inhaler, ask your health care professional to show you what to do.

To load the inhaler:

• Pull off the blue cover. Make sure the mouthpiece is clean and free of foreign objects.
• Pull the white mouthpiece until the tray is extended.
• Hold the corners of the white tray and pull out gently until you can see all the raised ridges on the sides of the tray.
• Put your finger and thumb on the ridges, squeeze inward, and gently pull the tray out of the body of the inhaler.
• Place a disk on the wheel and then slide the tray back into the inhaler
• To replace the empty disk with a full disk, follow the same steps you used to load the inhaler.

To use the inhaler:

• Hold the inhaler flat in your hand.
• A plastic needle will break the blister containing one inhalation of medicine. When the flap is raised as far as it will go, the blister will be pierced. Do not lift the flap if the cartridge is not in the inhaler. Doing this will break the needle and you will need a new inhaler.
• After the blister is broken open, close the lid. Keeping the inhaler flat and well away from your mouth, breathe out to the end of a normal breath.
• Raise the inhaler to your mouth, and place the mouthpiece in your mouth.
• Close your lips around the mouthpiece and tilt your head slightly back. Do not bite down on the mouthpiece. Do not block the mouthpiece with your teeth or tongue. Do not cover the air holes on the side of the mouthpiece.
• Breathe in through your mouth as steadily and as deeply as you can until you have taken a full deep breath.
• Hold your breath and remove the mouthpiece from your mouth. Continue holding your breath as long as you can up to 10 seconds before breathing out. This gives the medicine time to settle in your airways and lungs.
• Hold the inhaler well away from your mouth and breathe out to the end of a normal breath.
• Prepare the cartridge for your next inhalation. Pull the mouthpiece to extend the tray then push it in until it clicks. The disk will turn to the next dose. Do not pierce the blister until just before the inhalation.
• Take the second puff following exactly the same steps you used for the first puff.
• When you are finished, wipe off the mouthpiece and replace the cover to keep the mouthpiece clean and free of foreign objects.

Dosing

Follow your doctor's orders or the directions on the label.

• For treatment of flu (Influenza A and Influenza B)
  • Adults and children 7 years and older Two puffs twice daily (approximately 12 hours apart in the morning and evening) for 5 days. Two doses should be taken on the first day of treatment whenever possible provided there are at least 2 hours between doses. Zanamivir must be started within 48 hours after the onset of signs and symptoms of the flu.
• Canada: For treatment of flu (Influenza A and Influenza B)
  • Adults and children 12 years and older Two puffs twice daily (approximately 12 hours apart in the morning and evening) for 5 days. Two doses should be taken on the first day of treatment whenever possible provided there are at least 2 hours between doses. Zanamivir must be started within 48 hours after the onset of signs and symptoms of the flu.

Missed dose

This medicine works best when there is a constant amount in the lungs. To help keep the amount constant, do not miss any doses. If you miss a dose of this medicine, use it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses. It is best to take the doses at evenly spaced times day and night.

Storage

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Keep the medicine from freezing. Do not refrigerate.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Zanamivir will not keep you from spreading the flu virus to other people. This medicine may cause people with lung disease (chronic obstructive lung disease or asthma) to experience trouble breathing. If this should happen contact your doctor immediately. Zanamivir may not work in patients with lung disease, heart disease, or serious medical conditions.

Bronchospasm (wheezing) is a risk for patients with asthma or chronic respiratory disease. Always have a fast-acting inhaled bronchodilator available for your use.

Side Effects of This Medicine

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Stop using this medicine and get emergency help immediately if the following side effects occur:

• Rare
  • Convulsions;  dizziness and fainting ;  heartbeat, fast, slow, or irregular ;  increased sensitivity to sunlight;  itching, pain, redness, swelling or watering of eye or eyelid;  flushing or reddening of skin;  joint pain;  severe skin rash or hives;  shortness of breath or troubled breathing;  swelling or puffiness of face;  swollen glands or tightness in throat;  tightness in chest or wheezing 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• Less common

• Change in hearing;  cough;  cough producing mucus;  diarrhoea;  dizziness;  earache ;  ear drainage;  ear, nose and throat infections;  headache;  nasal signs and symptoms;  nausea;  pain and pressure over cheeks;  pain in ear;  shortness of breath;  tightness in chest ;  vomiting;  wheezing 

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although this use is not included in product labelling, zanamivir is used in certain patients:

• To prevent the infection caused by the flu virus (influenza A or influenza B).

Other than the above information, there is no additional information relating to proper use, precautions, or side effects for this use.

In the U.S. & Canada

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Category Antiviral