In addition to Tamiflu, Amantadine and Rimantadine are effective drugs against Influenza A and should be kept handy during the coming flu season. These compounds inhibit the activity of the influenza virus M2 protein, which forms a channel in the virus membrane. As a result, the virus cannot replicate after it enters the host. Relenza, an inhaler is used to treat Influenza A and Influenza B, the two types most responsible for flu epidemics. Patients needed to start treatment within two days of the onset of symptoms.