The Centers for Disease Control and Prevention (CDC) has released interim guidance for prioritizing oseltamivir for the treatment of influenza due to anecdotal reports indicating availability issues in some locations. 

The issue appears to be related to the availability of generic oseltamivir. At this time, the Food and Drug Administration (FDA) has not indicated shortages of the drug (generic or brand) in any of its forms. In settings where oseltamivir is currently unavailable, influenza testing is highly recommended to guide antiviral treatment.

If oseltamivir is unavailable, oral baloxavir, inhaled zanamivir, or intravenous (IV) peramivir can be used for early treatment of outpatients at increased risk for complications who present with uncomplicated influenza, depending upon age and contraindications. Patients with clinically mild influenza who are otherwise healthy and not at increased risk of influenza complications should be managed with supportive care without antivirals.

For hospitalized patients with suspected or laboratory-confirmed influenza, oseltamivir should be prioritized as it is the only antiviral recommended for treating influenza in this population. There is limited data for using inhaled zanamivir, IV peramivir, or baloxavir in hospitalized patients.

Once availability issues have been resolved, the CDC recommends reverting back to the original antiviral recommendations.

Oseltamivir is available as 30mg, 45mg, and 75mg capsules and 60mL oral suspension containing 6mg/mL. In hospitalized patients, oseltamivir can be administered orally or enterically via oro- or nasogastric tube. For children who are unable to swallow oseltamivir capsules, the capsules can be opened and mixed with a thick sweetened liquid. 

Reference

Interim guidance for clinicians to prioritize antiviral treatment of influenza in the setting of reduced availability of oseltamivir. News release. Centers for Disease Control and Prevention. Accessed December 15, 2022. https://emergency.cdc.gov/han/2022/han00482.asp.