famciclovir
noun
fam·ci·clo·vir
| \ ˌfam-ˈsī-klō-ˌvir
\
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Medical Definition of famciclovir
: a precursor C14H19N5O4 of the antiviral agent penciclovir that after oral administration is converted to penciclovir by cellular kinases and that is used especially to treat shingles and herpes genitalis — see famvir