Valacyclovir: Development, treatment and pharmacokinetics.

Acyclovir a specific and selective inhibitor of herpes virus has been used safely and effectively. The bioavailability of the drug is low results in poor absorption of drug. Valacyclovir is the L- valyl ester prodrug of Acyclovir. It is used in the treatment of Herpes simplex virus and Varicella zoster virus. After oral administration it is rapidly converted to acyclovir in the Gastro intestinal tract and liver, which increases the bioavailability of acyclovir three to five times that of acyclovir alone.