Drug Detail:Zanamivir (Zanamivir [ zan-am-i-vir ])
Drug Class: Inhaled anti-infectives Neuraminidase inhibitors
Usual Adult Dose for Influenza
10 mg via oral inhalation twice a day for 5 days
Comments:
- This drug should be started within 48 hours after onset of symptoms.
- If possible, 2 doses should be taken on the first day, provided there are at least 2 hours between the doses.
- After the first day, doses should be about 12 hours apart (e.g., morning and evening) at about the same time each day.
- Safety and efficacy of repeated courses of therapy have not been studied.
Use: For the treatment of uncomplicated acute illness due to influenza A and B virus in patients symptomatic for no more than 2 days
Usual Adult Dose for Influenza Prophylaxis
10 mg via oral inhalation once a day
Duration of Therapy:
- Household setting: 10 days
- Community outbreak: 28 days
Comments:
- Dose should be administered at about the same time each day.
- Household setting: No data available on the efficacy of prophylaxis with this drug when started more than 1.5 days after onset of signs/symptoms in the index case.
- Community outbreak: No data available on the efficacy of prophylaxis with this drug when started more than 5 days after the outbreak was identified in the community.
- Safety and efficacy of prophylaxis with this drug not evaluated for durations exceeding 28 days.
Use: For prophylaxis of influenza
Usual Pediatric Dose for Influenza
7 years or older: 10 mg via oral inhalation twice a day for 5 days
Comments:
- This drug should be started within 48 hours after onset of symptoms.
- If possible, 2 doses should be taken on the first day, provided there are at least 2 hours between the doses.
- After the first day, doses should be about 12 hours apart (e.g., morning and evening) at about the same time each day.
- Safety and efficacy of repeated courses of therapy have not been studied.
Use: For the treatment of uncomplicated acute illness due to influenza A and B virus in patients symptomatic for no more than 2 days
Usual Pediatric Dose for Influenza Prophylaxis
5 years or older: 10 mg via oral inhalation once a day
Duration of Therapy:
- Household setting: 10 days
- Community outbreak: 28 days
Comments:
- Dose should be administered at about the same time each day.
- Household setting: No data available on the efficacy of prophylaxis with this drug when started more than 1.5 days after onset of signs/symptoms in the index case.
- Community outbreak: No data available on the efficacy of prophylaxis with this drug when started more than 5 days after the outbreak was identified in the community.
- Safety and efficacy of prophylaxis with this drug not evaluated for durations exceeding 28 days.
Use: For prophylaxis of influenza
Renal Dose Adjustments
No adjustment recommended.
Comments:
- Safety and efficacy not established in severe renal dysfunction.
- Due to low systemic bioavailability of this drug after oral inhalation, no dose adjustment needed with renal dysfunction; potential for drug accumulation should be considered.
Liver Dose Adjustments
Data not available
Precautions
CONTRAINDICATIONS:
History of allergic reaction to any of the ingredients, including milk proteins
Safety and efficacy for treatment and prophylaxis of influenza have not been established in patients younger than 7 and 5 years, respectively.
Consult WARNINGS section for additional precautions.
Dialysis
Data not available
Other Comments
Administration advice:
- The 10 mg dose is provided by 2 inhalations (one 5 mg blister per inhalation).
- For administration to the respiratory tract by oral inhalation only, using the included inhalation device
- Instruct patients/supervising adults in the use of the delivery system.
- Do not puncture any blisters of the drug until administering a dose using the included inhalation device.
- Consult the manufacturer product information regarding missed doses.
General:
Limitations of Use:
- This drug is not recommended for treatment or prophylaxis of influenza in patients with underlying airways disease (e.g., asthma, chronic obstructive pulmonary disease) due to risk of serious bronchospasm.
- This drug has not been proven effective for treatment in patients with underlying airways disease or as prophylaxis in nursing home residents.
- This drug is not a substitute for annual, early influenza vaccination as recommended by the US CDC Advisory Committee on Immunization Practices.
- As influenza viruses change over time, resistant or more virulent mutations may emerge and decrease the efficacy of antiviral drugs; available influenza drug susceptibility patterns and treatment effects should be considered when deciding whether to use this drug.
- No evidence of efficacy in any illness due to pathogens other than influenza virus A and B.
Monitoring:
- Psychiatric: For signs of abnormal behavior in patients with influenza
- Respiratory: Respiratory function in patients with underlying airways disease
Patient advice:
- Read the US FDA-approved patient labeling (Patient Information and Instructions for Use).
- Stop this drug and contact healthcare provider if respiratory symptoms increase during therapy (e.g., worsening wheezing, shortness of breath, other signs/symptoms of bronchospasm).
- If scheduled to use an inhaled bronchodilator at the same time as this drug, use the bronchodilator before using this drug.
- Watch for signs of unusual behavior; contact healthcare professional immediately if any signs of unusual behavior are seen.
- If prescribed for children, use only under adult supervision and instruction.
- Use of this drug for treatment of influenza has not been shown to reduce the risk of transmission of influenza to others.
