Content on this page was developed during the 2009-2010 H1N1 pandemic and has not been updated.
- The H1N1 virus that caused that pandemic is now a regular human flu virus and continues to circulate seasonally worldwide.
- The English language content on this website is being archived for historic and reference purposes only.
- For current, updated information on seasonal flu, including information about H1N1, see the CDC Seasonal Flu website.
Antiviral Safety Information
December 24, 2009 1:30 PM ET
CDC: Updated Interim Recommendations for the Use of Antiviral Medications in the Treatment and Prevention of Influenza for the 2009-2010 Season: Adverse Events and Contraindications
This section of the Antiviral Recommendations summarizes the most recent safety information on antiviral agents.
CDC: Antiviral Agents for Seasonal Influenza: Side Effects and Adverse Reactions
General safety information on antiviral agents currently approved for use in influenza.
Emergency Use Authorization (EUA) for Tamiflu®: Fact Sheet for Healthcare Providers
The Food and Drug Administration (FDA) has issued an EUA for the use of oseltamivir in patients younger than 1 year of age, for use in patients who are symptomatic for more than 2 days, and use in patients with complicated illness requiring hospitalization due to the 2009 H1N1 influenza virus. Please consult this Fact Sheet for general information on possible side effects of oseltamivir.
Compounding Oseltamivir Suspension – Potential Dosing Errors
In the event that commercial supplies of Tamiflu® Oral Suspension are limited, oseltamivir 75 mg capsules can be compounded at most retail pharmacies. The commercially-manufactured Tamiflu® Oral Suspension concentration is 12 mg/mL; the compounded suspension concentration is 15 mg/mL.
- Commercial Tamiflu® Oral Suspension – Potential Dosing Device Errors
An oral dosing dispenser with 30 mg, 45 mg, and 60 mg graduations is provided with Tamiflu® Oral Suspension, rather than graduations in milliliters (mL) or teaspoons (tsp). When dispensing commercially-manufactured Tamiflu® Oral Suspension, pharmacists should ensure the units of measure on the prescription instructions match the dosing device. When dispensing Tamiflu® Oral Suspension for children younger than 1 year of age, or whose dose is less than 30 mg, the oral dosing dispenser that is included in the Tamiflu® product package should always be removed and an oral syringe that is capable of accurately measuring the prescribed dose in milliliters (mL) should be provided.
Emergency Use Authorization (EUA) for Relenza®: Fact Sheet for Healthcare Providers
The Food and Drug Administration (FDA) has issued an EUA for the use of zanamivir in patients with severe illness. Please consult this Fact Sheet for general information on possible side effects of zanamivir.
Relenza® Inhalation Powder – Warning: Powder Must Not Be Nebulized
The commercial formulation of Relenza® Inhalation Powder is not designed or intended for reconstitution in any liquid formulation and is not recommended for use in any nebulizer or mechanical ventilator.
Emergency Use Authorization (EUA) for Peramivir IV: Fact Sheet for Healthcare Providers
The Food and Drug Administration (FDA) has issued an EUA for the use of the unapproved (investigational) drug intravenous Peramivir for treatment of 2009 H1N1 influenza virus in certain hospitalized adult and pediatric patients. Data on the safety of Peramivir IV are limited. Please consult this Fact Sheet for general information on possible side effects of Peramivir IV. Healthcare providers who prescribe Peramivir IV are responsible for mandatory reporting to FDA MedWatch of all medication errors and selected adverse events occurring during Peramivir IV treatment within 7 calendar days from the onset of the event. The fact sheet includes information on what selected adverse events should be reported to FDA MedWatch.
- General Information on the EUA for Peramivir IV
- Antiviral Treatment Options, Including Intravenous Peramivir, for Treatment of Influenza in Hospitalized Patients for the 2009-2010 Season
Recommendations for Use of Antiviral Medications for the Management of Influenza in Children and Adolescent for the 2009-2010 Season -- Pediatric Supplement for Health Care Providers
This supplement provides recommendations for health care providers of children and adolescents on the use of antiviral medications for the treatment and chemoprophylaxis of influenza including 2009 H1N1 influenza infection and seasonal influenza.
Rare Neuropsychiatric Events in Children
Rarely, transient neuropsychiatric events (delirium, hallucinations, abnormal behavior) have been reported in postmarketing surveillance among persons taking oseltamivir and zanamivir. The majority of reports were among children and adolescents living in Japan. Because influenza infection itself can be associated with a variety of neurologic and behavioral symptoms, including seizures, delirium, and hallucinations, the contribution of the neuraminidase inhibitors to these neuropsychiatric effects is unclear. Until additional data are available, FDA advises that persons receiving neuraminidase inhibitors be monitored for abnormal behavior.
While oseltamivir and zanamivir are "Pregnancy Category C" medications, the available risk-benefit data indicate pregnant women with suspected or confirmed influenza should receive prompt antiviral therapy.
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