Zanamivir

Generic Name: zanamivir (zan AM i vir)Brand Names: Relenza

What is zanamivir?

Zanamivir is an antiviral medication. It blocks the actions of viruses in your body.

Zanamivir is used to treat flu symptoms caused by influenza virus in patients who have had symptoms for less than 2 days. Zanamivir may also be given to prevent influenza in people who may be exposed but do not yet have symptoms. Zanamivir will not treat the common cold.

Zanamivir may also be used for purposes other than those listed in this medication guide.

What is the most important information I should know about zanamivir?

Do not use a nebulizer or ventilator to give zanamivir. Zanamivir inhalation powder should never be mixed with a liquid.

Zanamivir is used to treat flu symptoms caused by influenza virus in patients who have had symptoms for less than 2 days. Zanamivir may also be given to prevent influenza in people who may be exposed but do not yet have symptoms. Zanamivir will not treat the common cold.

Treatment with zanamivir should start as soon as possible when flu symptoms appear, such as fever, chills, muscle aches, sore throat, and runny or stuffy nose.

Do not use this medication to treat flu symptoms in a child younger than 7 years old. Children as young as 5 may use the medication to prevent flu symptoms. Do not use an inhaled nasal flu vaccine (FluMist) within 2 weeks before or 48 hours after using zanamivir. Zanamivir may interfere with the drug action of FluMist, making the vaccine less effective. Follow your doctor's instructions. Before using zanamivir, tell your doctor if you have asthma, chronic obstructive pulmonary disease (COPD), or any other chronic lung condition. Serious or life-threatening bronchospasm (difficulty breathing) and other effects on the lungs can occur while using zanamivir. Stop using zanamivir and call your doctor at once if you have wheezing or severe breathing problems.

If you have asthma, COPD, or other chronic lung disease, make sure you have a fast-acting inhaled bronchodilator available to treat any serious breathing problems that may occur while using zanamivir. Fast-acting bronchodilators include albuterol (Ventolin, Proventil), bitolterol (Tornalate), metaproterenol (Alupent), and pirbuterol (Maxair). Talk with your doctor about which medicine is best for you.

Some people using zanamivir have had rare side effects of confusion, delirium and self-injury. These symptoms have occurred most often in children. It is not known whether zanamivir was the exact cause of these symptoms. However, anyone using zanamivir should be watched closely for signs of confusion or unusual behavior. Call a doctor at once if you or the child using zanamivir has any of these symptoms. Zanamivir should not be used in place of getting a yearly flu shot. The Centers for Disease Control recommends an annual flu shot to help protect you each year from new strains of influenza virus.

What should I discuss with my healthcare provider before using zanamivir?

Zanamivir should not be used in place of getting a yearly flu shot. The Centers for Disease Control recommends an annual flu shot to help protect you each year from new strains of influenza virus.

You should not use this medication if you are allergic to zanamivir or to lactose. Do not use zanamivir without first talking to your doctor if you have asthma, chronic obstructive pulmonary disease (COPD), or any other chronic lung condition. Serious or life-threatening bronchospasm (difficulty breathing) and other effects on the lungs can occur while using zanamivir.

If you have asthma, COPD, or other chronic lung disease, make sure you have a fast-acting inhaled bronchodilator available to treat any serious breathing problems that may occur while using zanamivir. Fast-acting bronchodilators include albuterol (Ventolin, Proventil), bitolterol (Tornalate), metaproterenol (Alupent), and pirbuterol (Maxair). Talk with your doctor about which medicine is best for you.

If you are scheduled to use a bronchodilator at the same time as zanamivir, use the inhaler first.

FDA pregnancy category C. It is not known whether zanamivir is harmful to an unborn baby. However, not receiving this medication to prevent influenza could be harmful to the baby if the mother becomes infected with a disease that zanamivir could prevent. Before taking this medication, tell your doctor if you are pregnant. Your doctor will decide whether you should receive zanamivir, especially if you have a high risk of infection with H1N1 influenza (also called "swine" flu). It is not known whether zanamivir passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby. Do not use this medication to treat flu symptoms in a child younger than 7 years old. Children as young as 5 may use the medication to prevent flu symptoms.

How should I use zanamivir?

Use this medication exactly as it was prescribed for you. Do not use the medication in larger amounts, or use it for longer than recommended by your doctor. Follow the directions on your prescription label.

Treatment with zanamivir should start as soon as possible when flu symptoms appear, such as fever, chills, muscle aches, sore throat, and runny or stuffy nose.

Zanamivir is packaged in disk-shaped foil packs that contain 4 blisters of medicine. These disks are placed into a device called a DISKHALER that you will use to inhale the medicine. The device opens and loads a blister of zanamivir each time you use the inhaler. The disk device is not to be used with a spacer. Follow the patient instructions provided with the DISKHALER.

Do not use a nebulizer or ventilator to give zanamivir. Zanamivir inhalation powder should never be mixed with a liquid. Do not use any other medicines in the DISKHALER. Always put the cover back on the device when not in use.

To treat flu symptoms: Use 2 inhalations every 12 hours for 5 days. Your doctor may tell you to use two doses on the first day of treatment, spaced at least 2 hours apart. On the following days, the doses should be spaced 12 hours apart. Follow your doctor's instructions.

To prevent flu symptoms: Use 2 inhalations every 24 hours for 10 to 28 days. Follow your doctor's instructions.

If you have a chronic respiratory disease such as asthma or COPD and you are scheduled to use an inhaled bronchodilator at the same time as zanamivir, use the inhaled bronchodilator before using zanamivir.

Use this medication for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Tell your doctor if your symptoms do not improve, or if they get worse. Store zanamivir at room temperature away from moisture and heat. Throw away the DISKHALER after your treatment ends.

What happens if I miss a dose?

Use the medication as soon as you remember. If it is within 2 hours of your next dose, skip the missed dose and use the medicine at the next regularly scheduled time. Do not use extra medicine to make up the missed dose.

Call your doctor if you miss several doses.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

What should I avoid while using zanamivir?

Do not use an inhaled nasal flu vaccine (FluMist) within 2 weeks before or 48 hours after using zanamivir. Zanamivir may interfere with the drug action of FluMist, making the vaccine less effective. Follow your doctor's instructions.

Zanamivir side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Some people using zanamivir have had rare side effects of confusion, delirium and self-injury. These symptoms have occurred most often in children. It is not known whether zanamivir was the exact cause of these symptoms. However, anyone using zanamivir should be watched closely for signs of confusion or unusual behavior. Call a doctor at once if you or the child using zanamivir has any of these symptoms. Stop using zanamivir and call your doctor at once if you have wheezing or severe breathing problems.

Less serious side effects may include:

  • headache;

  • dizziness;

  • nausea, vomiting, or diarrhea;

  • infection of your ear, nose, or throat;

  • stuffy or irritated nose; or

  • cough or respiratory symptoms.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Zanamivir Dosing Information

Usual Adult Dose for Influenza:

10 mg (2 inhalations) inhaled orally twice a day (12 hours apart) for 5 daysIf possible, 2 doses should be taken on the first day, provided there are at least 2 hours between the doses.

Usual Adult Dose for Influenza Prophylaxis:

10 mg (2 inhalations) inhaled orally once a dayDuration:Household setting: 10 daysCommunity outbreak: 28 days

Usual Pediatric Dose for Influenza:

7 years or older: 10 mg (2 inhalations) inhaled orally twice a day (12 hours apart) for 5 daysIf possible, 2 doses should be taken on the first day, provided there are at least 2 hours between the doses.

Usual Pediatric Dose for Influenza Prophylaxis:

5 years or older: 10 mg (2 inhalations) inhaled orally once a dayDuration:Household setting: 10 daysCommunity outbreak: 28 days

What other drugs will affect zanamivir?

There may be other drugs that can interact with zanamivir. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Where can I get more information?

  • Your pharmacist can provide more information about zanamivir.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.
Copyright 1996-2006 Cerner Multum, Inc. Version: 10.01. Revision Date: 11/11/2009 11:32:55 AM.
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