Dose Age adults and children 12 years of age and over kids under 12 years of age one packet don't use. Do not take more than three packets in 24 hours until directed by a health care provider. See how Advil delivers superior aid for widespread cold and flu signs. One-dose XOFLUZA may help alleviate flu signs in sufferers aged 5 years and older—but the window of forty eight hours for prescription remedy...