Zanamivir Inhaler: Uses, Dosage, Side Effects, Precautions and Alternates

Quick overview

Zanamivir Inhaler (generic name: zanamivir) is an antiviral agent from the neuraminidase inhibitor class, used to treat or prevent influenza caused by influenza A and B viruses. It comes as a dry powder in blister packs that is inhaled using a special device called a Diskhaler. It is used in adults and children 7 years and older, either to treat flu symptoms that have lasted no more than 2 days or to help prevent flu after exposure or during an outbreak.

What is Zanamivir Inhaler

Zanamivir is an inhaled antiviral powder used to treat or prevent influenza (flu) caused by influenza A and B viruses. It comes as a dry powder in blister packs that you inhale using a special device called a Diskhaler.

Zanamivir Inhaler uses

• Treatment of uncomplicated flu (influenza A and B) in adults and children 7 years and older who have had symptoms for no more than 2 days
• Prevention of flu in adults and children 7 years and older, including after contact with someone who has the flu or during a community flu outbreak

Benefits of Zanamivir Inhaler

• Can shorten how long flu symptoms last, generally by one to two days
• May help you feel better sooner
• Can lower the chance of getting the flu after being around someone who is infected
• Can reduce the chance of getting the flu during a community outbreak

How Zanamivir Inhaler works

The flu virus uses an enzyme called neuraminidase to spread from infected cells to healthy cells in your airways. Zanamivir blocks this enzyme, which stops the virus from spreading further in your respiratory tract. With less virus around, your body doesn't have to fight as hard, so your symptoms should improve faster.

Zanamivir Inhaler dosage

Zanamivir is taken by oral inhalation only, using the Diskhaler device provided. Do not swallow the powder, mix it with liquid, or use any other inhaler device. For treatment, doses are usually taken about 12 hours apart, at the same times each day, though the first day's doses may be closer together. For prevention, the dose is usually taken once daily at around the same time each day.

Finish the full course of treatment or prevention as prescribed, even if you start to feel better. Start treatment as soon as possible after symptoms begin, ideally within 2 days of symptom onset, for the best benefit.

If you use another inhaled medicine (such as a bronchodilator for asthma or COPD) at the same time, use that inhaler first, then wait a few minutes before using zanamivir. Children using this medicine should always be supervised by an adult who understands how to use the device properly. Sit down in a relaxed position before inhaling a dose, and only hold your breath for as long as feels comfortable afterward. If you feel unwell, it's a good idea to have someone with you while you inhale a dose, in case you feel faint or lightheaded.

Available forms and strengths

• Inhaler

Side effects of Zanamivir Inhaler

Common

• Headache
• Diarrhea
• Nausea
• Vomiting
• Appetite problems
• Nasal irritation/congestion or runny nose
• Bronchitis
• Cough
• Sinusitis
• Ear, nose, and throat infections
• Fever
• Chills
• Body/muscle pain
• Fatigue
• Dizziness
• Itchy skin rash
• Sore throat

Serious

• Bronchospasm (wheezing, difficulty breathing, shortness of breath, chest tightness)
• Allergic reactions including facial or throat swelling, hives, anaphylaxis
• Severe skin reactions such as erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis (widespread blistering or peeling skin)
• Fainting or feeling very lightheaded after inhaling a dose
• Seizures, hallucinations, confusion, delirium, or sudden abnormal behavior (especially in children and teens)
• Irregular or fast heartbeat

Warnings and precautions

• Some people using zanamivir have had serious breathing problems, including wheezing and worsening lung function, sometimes leading to hospitalization or death. This happens more often in people who already have asthma or chronic obstructive pulmonary disease (COPD), but it has occurred in others too. Stop the medicine and get medical help right away if breathing problems occur.
• This medicine is not generally recommended for people with severe asthma or severe COPD because it hasn't been proven safe and effective in this group, and the risk of serious breathing problems is a concern.
• Never turn the inhaled powder into a liquid solution for use in a nebulizer or breathing machine. Doing this has caused serious harm, including a death, because the lactose in the powder can clog the equipment.
• Serious allergic reactions have occurred, including swelling of the face and throat, severe skin rashes, and life-threatening whole-body allergic reactions. Stop the medicine and get medical help immediately if this happens.
• People with the flu, especially children and teenagers, can have sudden changes in behavior, confusion, hallucinations, or seizures, which may or may not be related to the medicine. Close monitoring is important.
• This medicine does not replace your annual flu vaccination.
• This medicine contains lactose made with milk protein, so it should not be used by people allergic to zanamivir or to any ingredient in the powder, including milk protein.
• There isn't enough information to be certain about the safety of zanamivir in pregnancy, but having the flu while pregnant carries its own risks. Your doctor will help weigh the benefits and risks if you are pregnant or planning to become pregnant.
• It isn't known for certain whether zanamivir passes into human breast milk, but absorption into the mother's bloodstream is low, so exposure to a nursing infant is expected to be minimal. Your doctor can help you weigh the benefits and risks.
• People with kidney problems can have higher levels of the drug in their body because it's cleared from the body less quickly, though this matters less for the inhaled form than for injections. Tell your doctor if you have kidney disease.
• The effects of liver problems on zanamivir haven't been specifically studied, but tell your doctor if you have liver disease.

Storage

• Store at room temperature (15 to 30°C) in a dry place
• Use the Rotadisk/blister before the expiration date
• Do not puncture any blister until you are ready to inhale a dose
• Keep the medicine and Diskhaler device in a safe place away from children
• Dispose of unneeded medication through a medicine take-back program rather than flushing it down the toilet

When to see a doctor

• Stop using this medicine and get emergency medical help right away if you have sudden trouble breathing, wheezing, or tightness in your chest or throat.
• Get emergency help for signs of a serious allergic reaction, such as swelling of the face, mouth, or throat, hives, severe rash, or difficulty swallowing.
• Seek urgent medical care for a severe skin reaction such as blistering, peeling skin, or a rash that looks like targets (dark spots with pale rings).
• Call your doctor right away if you or your child becomes confused, shows unusual or abnormal behavior, has hallucinations, or has a seizure while taking this medicine or while sick with the flu.
• Contact your doctor if you feel worse, develop new symptoms, or your flu symptoms don't start improving during or after treatment.
• If you think you may have taken too much of this medicine, contact a healthcare professional, hospital emergency department, or your local poison control center right away, even if you don't have symptoms.

Alternatives

• Amantadine
• Peramivir
• Oseltamivir