Influenza (Flu)

Alerts, Advisories and Updates

ADVISORY - OSELTAMIVIR PRESCRIBING

21 October 2005

As concern about avian influenza builds, health care providers all over the country are getting requests for oseltamivir from individuals for whom it is not indicated. This practice may cause shortages, wastage, ¹ and widespread resistance. ²

Given both the scarcity of oseltamivir and questionable effectiveness in the treatment of avian influenza, ³ prescribing oseltamivir for individual stockpiling is inappropriate. There are limited supplies of oseltamivir in the U.S. Hoarding of this drug now because of concerns about a future pandemic may mean that oseltamivir becomes unavilable for those who need it most during the current regular flu season.

For up-to-date information on influenza see: http://www.health.ri.gov/flu/index.php

Notes

1. The average shelf life of oseltamivir available in Rhode Island is less than one year. The drug should not be used after its expiration date, especially if it has been stored in less-than-ideal conditions, as it may be ineffective. Inappropriate use of oseltamivir also wastes the drug. For example, people who have individual stockpiles may use oseltamivir for inappropriate indications, such as URIs.

2. Widespread use of oseltamivir for influenza will inevitably lead to drug resistance.

3. It is not clear that oseltamivir is effective in treating avian influenza A (H5N1). Many of the Southeast Asian patients who died of avian influenza A (H5N1) were taking oseltamivir.

Appropriate uses of oseltamivir for the 2005-2006 flu season:

1. Treatment of influenza during the 2005-2006 flu season. Recommended duration of treatment: 5 days.

Highest priority for treatment: Persons who are considered to be at highest risk from serious complications from influenza infection: persons >65 years, young children, and persons with certain chronic illnesses.

2. Chemoprophylaxis during the 2005-2006 flu season, limited to the following three groups:

a. Persons at highest risk (above) who are vaccinated after influenza activity has begun

b. Unvaccinated persons after influenza activity has begun, if they have frequent contact with persons at highest risk (above) during influenza season

c. Persons who have immune deficiencies

3. Control of documented influenza outbreaks in institutions during the 2005-2006 flu season.

All other uses of oseltamivir should be avoided during the 2005-2006 flu season.