Valaciclovir

Valaciclovir is a pro-drug of aciclovir. Acyclovir triphosphate competitively inhibits viral DNA polymerases and, to a much lesser extent, cellular DNA polymerases. Acyclovir triphosphate is incorporated into viral DNA, where it acts as a chain terminator due to the lack of a 3′- hydroxyl group, leading to irreversible inactivation of the viral DNA polymerase.

Renal adjustment

For treatment of herpes labialis (adults and children): if eGFR 30–50 mL/minute/1.73 m2, initially 1 g, then 1 g 12 hours after initial dose; if eGFR 10–30 mL/minute/1.73 m2, initially 500 mg, then 500 mg 12 hours after initial dose; if eGFR less than 10 mL/minute/1.73 m2, 500 mg as a single dose.…