GENERIC NAME: Zanamivir

COMMON BRAND: Relenza

Zanamivir is an oral inhalation prescription antiviral drug belongs to the class of medications known as a neuraminidase inhibitor. It works by inhibiting (neuraminidase of influenza virus) the spread of the flu virus in the body. Zanamivir, sold under the brand name “Relenza” used to treat and prevent uncomplicated acute influenza A and influenza B which is also known as “Swine Flu“. The most common flu virus in human is influenza A – H1N1 virus. This drug works by stopping the flu virus from spreading, but it is not an alternative for the yearly flu vaccine.

What is Zanamivir (Relenza) used for?

Treatment of Influenza (flu):

Zanamivir is used to treat acute uncomplicated influenza infection in adults and children 7 years and above who have had symptoms of flu (such as stuffy nose, cough, sore throat, fever/chills, aches, tiredness) not more than two days.

Prevention of Influenza (flu):

Zanamivir is also used to prevent influenza in adults and children above 7 years in case of exposure to an infected person with flu or if there is an outbreak.

How to use Zanamivir (Relenza)?

Before you start your treatment with zanamivir, and each time you get a refill, read the patient information guideline if available from your pharmacist.

Carefully read all the directions on the product information leaflet about how to prepare and inhale a dose of zanamivir using the Diskhaler. Seek advice from your prescriber or pharmacist if you have any questions about how to inhale this medication.

This drug comes in powder form to inhale with a plastic inhaler called a “Diskhaler” (a device for inhaling powder) and five Rotadisks (containing four sacs of medication). Use only this disk inhaler to inhale this drug. Do not mix it with any liquid, or inhale it with any other inhalation device.

Before taking this drug, make sure to remove the cover of the disk inhaler and check the mouthpiece to be clean and free of particles. Break one medication blister and load the medication into the disk inhaler. Place the mouthpiece into your mouth, and take a deep breath. This will help to draw the medicine into your lungs. If possible hold your breath for a few seconds. For next dose repeat the procedure and make sure to replace the cover of the disk inhaler.

If you have breathing problems like as asthma, emphysema, chronic obstructive pulmonary disease-COPD) and are scheduled to use inhaled bronchodilators (albuterol) at the same time as zanamivir, use the bronchodilator medication before using zanamivir. Talk to your doctor or pharmacist for further details.

If children are using this drug, parents or other responsible adults should supervise the children to make sure they use it correctly.

For flu treatment: It is inhaled by your mouth as directed by your doctor, usually 2 inhalations (1 blister per inhalation) twice a day for 5 days.

For flu prevention: It is inhaled by your mouth as directed by your doctor, usually 2 inhalations (1 blister per inhalation) once a day for 10 days if there is an outbreak, or you have been exposed to an infected person with flu.

Do not stop taking zanamivir without consulting your doctor, even if you feel better. Doing this may result in a return of the infection, or develop resistance against the flu virus.

Seek advice from your doctor if your symptoms get worse or new signs appears while taking this drug.

What are the side effects of taking Zanamivir (Relenza)?

A headache, dizziness, throat/tonsil pain, cough (because this medication is an inhaled powder) are the common side effects observed with the use of this drug. If these effects continue or get worse, notify your doctor or pharmacist promptly.

Hallucination, delirium, trouble speaking, abnormal bebehavior and self-injury have been noticed in patients with influenza who were receiving zanamivir. This effects may be more likely in children. Tell your doctor right away if you see any of the above symptoms.

A severe allergic reaction may occur with use of this drug. However, get emergency medical help right away if you notice any symptoms of a severe allergic reaction, such as rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, shortness of breath.

This is not a complete record of possible side effects. If you see other effects not listed above, contact your doctor or pharmacist promptly.

Zanamivir can cause breathing problems, in rare cases, it can be fatal. If you experience trouble breathing such as wheezing or breathlessness, stop using zanamivir and get medical help right away.

What are the precautions while using Zanamivir (Relenza)?

Notify your doctor or pharmacist if you are allergic to this medicine before starting the treatment; or if you have some other allergies. The product containing zanamivir may also include some other inactive ingredients (such as lactose, milk proteins), that may cause allergic reactions or other illness. Ask your doctor or pharmacist regarding further information about this medicine.

This medicine may cause anaphylaxis (a type of allergic reaction which may be fatal). Seek medical assistance immediately if you have a rash, itching, hoarseness, breathlessness, trouble swallowing, or any swelling of your face/mouth/hands while you or your child are using this medicine.

Notify your doctor or pharmacist about your medical history before the commencing the treatment with this medicine, especially if you have any lung or breathing problems (for example chronic obstructive pulmonary disease-COPD, asthma).

This drug may make you dizzy. Avoid using machinery, or doing anything that demands alertness. Do not use alcohol or marijuana with this medication as you may get dizzier.

Have a record of all the medications you might be using (including prescription, nonprescription drugs, and herbal products) and inform your doctor or dentist before having any surgery.

Children may not be able to breathe deep enough using this inhaler device to get enough dose of the drug to benefit them, and this may result in a decrease in effectiveness of the drug in young children.

This medication must be used only when clearly needed in pregnancy. Ask your doctor/pharmacist regarding the risks and benefits of this drug.

The information on whether this drug passes into breast milk is not known. Consult your doctor before breastfeeding.

What are the drug interactions of Zanamivir (Relenza)?

Zanamivir may interact with other medications, herbs, or vitamins you may be using. A drug interaction is when a substance changes the way a drug works which can be harmful or hinder the drug from working well.

Do not use a nasal flu vaccine within 48 hours after taking zanamivir. This medicine may interfere with the protection from flu vaccine given in the nose, Hence making the vaccine less effective. Inform your doctor if you have received the flu vaccine in the nose.

WARNINGS:

Severe Skin/Hypersensitivity Reactions:

Cases of anaphylaxis (severe allergic reaction can lead to anaphylactic shock) and severe skin reactions including toxic epidermal necrolysis, Stevens-Johnson Syndrome (allergic reaction of face/tongue/throat with breathlessness) and erythema multiforme have been reported with zanamivir. This drug is not prescribed to people with any severe known hypersensitivity.

Neuropsychiatric Events:

Neuropsychiatric symptoms like delirium and abnormal behaviour have been noticed in patients with influenza who were receiving this drug. Regularly monitor patients taking zanamivir for signs of unusual behaviour. Discontinue this drug seek immediate medical attention if neuropsychiatric symptoms occur.

Bacterial Infections:

Serious bacterial infections may occur with similar symptoms like influenza or may overlap with or occur as complications during the treatment of flu. Zanamivir does not help to prevent such complications.

What are the forms and strengths of Zanamivir (Relenza)?

Forms: Inhalation powder
Strength: 5mg (20 units per Rotadisk)

What is the dosage of Zanamivir (Relenza)?

For Treatment of Influenza A & B:

Adult (18 and above):

Regular dose: Inhale 10mg twice a day for 5 days. More extended treatment may be required in severely ill patients.

Pediatric:

Children (7 years and above):

Regular dose: Inhale 10mg twice a day for 5 days.

Dosing considerations:

Take this drug for acute, uncomplicated flu infection in patients having flu symptoms no more than 48 hours.
Take 2 doses of inhaler on day 1, at least 2 hours apart.

For Prevention of Influenza A and B:

Adult (18 and above):

Regular dose: Inhale 10mg of this drug once a day for 10 days if you are exposed to an infected person, initiate within 36 hours of exposure. In case of an outbreak, inhaled 10mg of this drug once a day for 28 days. Start within 5 days of the outbreak.

Pediatric:

Children (5 years and above):

Regular dose: Inhale 10mg once a day for 10 days if exposed to an infected person.

Children (12 to 16 year):

Regular dose: Inhale 10mg once a day for 28 days; start within 5 days of the community outbreak.

For Treatment of Swine Flu ( H1N1 Influenza A) (Off-label):

Adult (18 and above):

Regular dose: Inhale 10mg twice a day for 5 days. More extended treatment may be required in severely ill patients. Start within 48 hours onset of symptom take 2 doses on day 1, at least 2 hours apart.

Pediatric:

Children (7 years and above):

Regular dose: Inhale 10mg twice a day for 5 days.

For Prevention of Swine Flu ( H1N1 Influenza A) (Off-label):

Adult (18 and above):

Inhale 10mg of this drug once a day for 10 days if you are exposed to an infected person. Initiate within 7 days of exposure.

Pediatric:

Children (5 years and above):

Regular dose: Inhale 10mg once a day for 10 days if exposed to an infected person. Start within 48 hours of exposure.

Children (12 to 16 year):

Regular dose: Inhale 10mg once a day for 28 days; start within 5 days of the community outbreak.

Most common questions asked about Zanamivir (Relenza) / Q&A’s:

 Is Zanamivir (Relenza) better than Oseltamivir (Tamiflu)?

Zanamivir (Relenza) and Oseltamivir (Tamiflu) are usually used for the prevention and treatment of influenza in adults and children. Both drugs are widely used for the prevention and treatment of influenza in adults and children. These medications are used to prevent and reduce symptoms of flu by preventing the influenza virus from spreading inside the body.
At present, Oseltamivir (Tamiflu) is widely used against flu in patients 2 weeks and above whose symptoms have not lasted longer than 2 days. It is also used to prevent flu in patients 1 year and above.
Zanamivir (Relenza) is used for the treatment of flu in patients 7 years and above and also used in the prevention of flu in children 5 years and above.

Disclaimer

TheMedPharma has made every effort to make sure that all the information is factually correct, comprehensive, and up-to-date. However, this website should not be considered as a substitute for the advice, knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or licensed health care professional before taking any medication. The drug information contained herein is subjected to changes if required. The lack of warnings or other information for a given drug does not mean that the drug or its combination is safe, effective or appropriate for use in all patients.