The Centers for Disease Control yesterday issued an urgent health alert warning Americans not to rely on the antiviral drugs amantadine or rimantadine to treat influenza infection. The agency says a resistance to the medicines has developed in much of the US influenza A virus. Amantadine, however, is also used to treat Parkinson’s disease, and should continue to be used for this treatment. The discovery increases concern about preparedness for the bird flu, since the newer antiviral drugs – Tamiflu and Relenza – were being conserved for use in incidences of avian flu, if it should come to the US. Now, the government is recommending these two drugs be used for the treatment of seasonal flu.There is some concern a resistance to these drugs will now begin to develop.The older, and now ineffective drugs, worked only against the type A influenza but are less expensive and also available in generic forms. Tamiflu and Relenza work against type A and type B influenza and have shown some promise in treating bird flu.CDC officials held an unusual Saturday news conference to release the warning.
