<unk>  is a guanosine analogue antiviral drug used for the treatment of various herpesvirus infections, most commonly for herpes zoster (shingles). It is a prodrug form of penciclovir with improved oral bioavailability.<unk>  is marketed under the trade name Famvir (Novartis).<unk>  was patented in 1983 and approved for medical use in 1994. In 2007, the United States Food and Drug Administration approved the first generic version of<unk> . Generic tablets are manufactured by TEVA Pharmaceuticals and Mylan Pharmaceuticals.
Famciclovir
Aciclovir
Penciclovir
Valganciclovir
Ganciclovir
Alcaftadine
Amantadine
Rimantadine