Answer: C
There are two classes of antiviral medications for influenza. The first class to be discovered was the adamantine derivatives (amantadine and rimantadine). A more recent class of antiviral drugs is the neuraminidase inhibitors (oseltamivir and zanamivir). All are taken orally except for zanamivir, which is inhaled. Treatment is generally reserved for those populations who are at high risk for a more severe course of influenza infection such as those older than 65 years or younger than 2 years, those with chronic lung or cardiac disease, immunocompromised, and pregnant individuals. While oseltamivir initially was not approved for use in children younger than 1 year old because of concerns about neurological side effects, in 2012 the U.S. Food and Drug Administration (FDA) expanded the approved use of oseltamivir to treat children as young as 2 weeks old who have shown symptoms of flu for no longer than two days.
Oseltamivir (D) has been assigned to pregnancy category C by the FDA and is approved for use in newborns at 2 weeks old, but not immediately after birth. The older drugs, amantadine (A) and rimantadine, although approved for treatment and prevention of influenza A are rarely used since many strains of influenza, including the 2009 H1N1 influenza, are now resistant to these two drugs and all influenza B strains are resistant. Oseltamivir acts as a neuraminidase inhibitor (B). Reverse-transcriptase inhibitors (RTIs) are a class of antiretroviral drugs used to treat HIV infection and other retroviruses.
Reference
Wang K, Shun-Shin M, Gill P, Perera R, Harnden A . “Neuraminidase inhibitors for preventing and treating influenza in children”. In Harnden, Anthony. Cochrane Database Syst Rev 4 (2012)
“Oseltamivir phosphate, Review, and Labeling Information”. Drugs@FDA. U.S. Food and Drug Administration (FDA).
