Although receiving annual influenza vaccinations is the best way to prevent flu, antiviral chemoprophylaxis is an important adjunct to flu prevention. Whereas the CDC does not recommend the routine use of antiviral medications as chemoprophylaxis for influenza exposures, antiviral chemoprophylaxis can be considered to help prevent flu in certain situations.7
Who to Chemoprophylax
Antiviral medications can be considered for chemoprophylaxis when you want to prevent influenza in a patient at high risk for complications who:
- Is exposed to influenza during the first 2 weeks after receiving an inactivated influenza vaccine
- Cannot receive an influenza vaccination after an exposure to influenza or
- Might not have responded to the influenza vaccination after exposure to a person with influenza.7
When to Chemoprophylax
In general, antiviral chemoprophylaxis is not recommended >48 hours after a patient’s first exposure to a person with influenza.7
How to Chemoprophylax
- Only oral oseltamivir and inhaled zanamivir are recommended for influenza chemoprophylaxis.7 See the recommended antiviral medication table.
- The recommended antiviral chemoprophylaxis course for influenza is once daily oral oseltamivir or inhaled zanamivir for the duration of potential exposure to a person infected with influenza and an additional 7 days after the last known exposure.7 See the antiviral dosing and duration table.
For more information on medication dosing, chemoprophylaxis in institutional settings or hospitals, chemoprophylaxis for health care personnel, treatment in the inpatient setting, timing considerations for concomitant influenza vaccination and antiviral therapy, or additional management considerations, please see the CDC’s influenza antiviral medications webpage.