In this Article

• What is zanamivir (Relenza)?
• What are the possible side effects of zanamivir (Relenza)?
• What is the most important information I should know about zanamivir (Relenza)?
• What should I discuss with my healthcare provider before using zanamivir (Relenza)?
• How should I use zanamivir (Relenza)?
• What happens if I miss a dose (Relenza)?
• What happens if I overdose (Relenza)?
• What should I avoid while using zanamivir (Relenza)?
• What other drugs will affect zanamivir (Relenza)?
• Where can I get more information?

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

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.

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.

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 will harm 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. 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 (Relenza)?

Use exactly as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended. 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 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 full prescribed length of time. Your symptoms may improve before the infection is completely cleared. 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.