Peniclover

Penciclovir undergoes activation by viral thymidine kinase, and the triphosphate form inhibits DNA polymerase but does not cause chain termination is an acyclic guanosine nucleoside derivative that is active against HSV-1, HSV-2, and VZV. Penciclovir is only administered topically It is monophosphorylated by viral thymidine kinase, and cellular enzymes form the nucleoside triphosphate, which inhibits HSV DNA polymerase. Penciclovir triphosphate has an intracellular half-life 20 to 30-fold longer than does acyclovir triphosphate. Penciclovir is negligibly absorbed upon topical application and is well tolerated. Both pain and healing are shortened by approximately half a day in duration