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Related to zanamivir: amantadine, Oseltamivir, Relenza


an inhibitor of viral neuraminidase used for the prophylaxis and treatment of influenza A and influenza B; administered by inhalation.



Pharmacologic class: Neuraminidase inhibitor

Therapeutic class: Antiviral

Pregnancy risk category C


Inhibits influenza virus neuraminidase, an enzyme essential for viral replication


Powder for inhalation: 5 mg/blister

Indications and dosages

Prevention of influenza

Adults and children ages 5 and older: Prophylaxis in the household setting, 2 inhalations (10 mg) once daily for 10 days. Prophylaxis during community outbreaks, 2 inhalations (10 mg) once daily for 28 days.

Influenza virus A or B

Adults and children ages 7 and older: Two oral inhalations (5 mg/inhalation) b.i.d. for 5 days


• History of allergic reaction to components of drug, including lactose milk proteins


Use cautiously in:

• chronic obstructive pulmonary disease, asthma, lactose intolerance

• concurrent use of live attenuated intranasal influenza vaccine (Don't administer until 48 hours after cessation of zanamivir and don't administer zanamivir until 2 weeks after administration of live attenuated influenza vaccine, unless medically indicated.)

• pregnant or breastfeeding patients

• children younger than age 7 (safety not established).


• Give two doses on day 1, spaced at least 2 hours apart. On subsequent days, space doses 12 hours apart, and give at approximately same time each day.

Adverse reactions

CNS: headache, dizziness

EENT: sinusitis, EENT infections

GI: nausea, vomiting, diarrhea

Respiratory: bronchitis, cough

Other: allergic reaction


None significant

Patient monitoring

• Assess respiratory status. Watch closely for signs and symptoms of declining respiratory function.

Patient teaching

• Explain therapy to patient. Demonstrate how to use Diskhaler device.

• Tell patient to take drug exactly as prescribed for as long as directed, even if symptoms improve.

• If patient is also taking an inhaled bronchodilator, advise him to take bronchodilator before zanamivir.

• Emphasize that drug doesn't prevent spread of influenza to others.

• Instruct patient to immediately report worsening respiratory symptoms.

• As appropriate, review other significant adverse reactions.


An agent that inhibits neuraminidase of influenza virus.


/za·nam·i·vir/ (zah-nam´ĭ-vir) an inhibitor of viral neuraminidase used for the prophylaxis and treatment of influenza A and B.


An antiviral drug, C12H20N4O7, that is used in inhalant form for the treatment and prevention of influenza.


an antiviral administered by oral inhalation.
indication Zanamivir is used in the treatment and prophylaxis of type A and B influenza in patients who have had symptoms for no more than 2 days.
contraindication Known hypersensitivity to this drug prohibits its use.
adverse effects Adverse reactions to this drug include fatigue, ear-nose-throat infections, diarrhea, nasal symptoms, cough, sinusitis, and bronchitis. Common side effects include headache, dizziness, nausea, and vomiting.


Relenza® Infectious disease An inhaled viral neuraminidase inhibitor used to treat and prevent influenza A and B infection. See Influenza. Cf Amantadine, Rimantidine.


A neuraminidase inhibitor antiviral drug used for the treatment of influenza A and influenza B. To be effective, the drug must be taken within 48 hours of the onset of symptoms. It is liable to cause tightening of the bronchial tubes and this may be dangerous in people with ASTHMA. A brand name is Relenza.
References in periodicals archive ?
A 2011 record linkage study in Sweden identified 86 pregnant women for whom oseltamivir (n=81) or zanamivir had been prescribed.
Recommended dosage of antiviral agents for treatment Age group Weight (kg) Oseltamivir Zanamivir dosage * dosage * Adults 75 mg twice per Two 5 mg day inhalations (10 mg total) twice per day Premature neonates ([dagger]) <38 weeks 1 mg/kg twice per day 38-40 weeks 1.
Although zanamivir tended to be well tolerated, oseltamivir was associated with an increased risk of nausea and vomiting, as well as a greater risk of psychiatric events when used as preventive therapy, the study found.
1 virus carried the mutation V149A, which was previously linked to slightly reduced susceptibility to zanamivir (18).
Two studies addressed hospitalization, and showed that patients with confirmed influenza or influenza-like illness who received zanamivir may be less likely to be hospitalized than patients who received no antiviral, a 34% reduction that was not statistically significant.
If a pregnant woman is exposed to influenza, 10 days of prophylactic antiviral therapy (75 mg oral oseltamivir or 10 mg inhaled zanamivir daily) is indicated.
20 January 2011 - UK GlaxoSmithKline (LON: GSK) said on Wednesday that the first patient has received treatment in a pivotal Phase III study of hospitalised patients with influenza which compares intravenous (IV) zanamivir to oral oseltamivir.
Dual treatment with oseltamivir and zanamivir was used when resistant virus was suspected or confirmed.
PREP Act declarations currently cover certain pandemic influenza countermeasures used to prevent, treat, or diagnose pandemic influenza such as influenza A (H1N1) 2009 monovalent vaccine, oseltamivir, zanamivir, peramivir, certain personal respiratory protection devices (e.
Intravenous zanamivir was obtained under the compassionate use program through GlaxoSmithKline.