Antiviral Drugs Should Be Used Cautiously to Fight Flu, U.S. Says

Sept. 9 -- TUESDAY, Sept. 8 (HealthDay News) -- Antiviral medications such as Tamiflu and Relenza, which are effective in treating the H1N1 swine flu, should be taken only by people hospitalized with the flu or those at high risk for complications from the disease, U.S. health officials said Tuesday.

Those at risk include people with underlying health conditions, such as asthma or diabetes, as well as the very young, the elderly, and pregnant women, officials said.

Because the H1N1 swine flu remains mild for the vast majority of people who get it, most people won't need these medications at all, according to new guidelines for antiviral drug use issued by the U.S. Centers for Disease Control and Prevention.

"Antiviral medicines are a critical part of our tool kit in countering influenza, both the 2009 H1N1 influenza virus and seasonal flu strains," Dr. Anne Schuchat, director of CDC's National Center for Immunization and Respiratory Diseases, said during an afternoon news conference.

But, Schuchat added, "most children, adolescents and adults who have influenza-like illness do not need antiviral medicine."

One reason why: If too many people take antiviral medicines it could increase the risk that the virus would become resistant to these drugs, Schuchat said.

"We have seen a bit of antiviral resistance already with the 2009 H1N1 strain, and we hope this won't take off," she said. "A critical feature is to use these antivirals very carefully so they can have benefit and not lead to problems."

Because most people who get the flu -- whether H1N1 swine flu or seasonal flu -- will not be tested to see what type of flu they have, the new guidelines are based on symptoms, not a particular flu strain, Schuchat said.

"A key point of the antiviral guidance is that hospitalized patients who are suspected to have influenza need prompt treatment with antiviral medicines," she said. "That can be a very important way to reduce the severity of illness. We don't want providers to wait until test results are available, but we want them to start antivirals when you suspect influenza."