Also Known As: Valtrex, Valaciclovir, Zelitrex, Valacyclovir
Valaciclovir (INN) or valacyclovir (USAN) is an antiviral drug used in the management of herpes simplex, herpes zoster (shingles), and herpes B. It is a prodrug, being converted in vivo to aciclovir. It is marketed by GlaxoSmithKline under the trade names Valtrex and Zelitrex. As of November 25, 2009 (2009 -11-25)[update], valacyclovir is marketed in generic form in the United States by Ranbaxy Laboratories.
Valaciclovir is indicated for the treatment of HSV and VZV infections, including:
- Oral and genital herpes simplex (treatment and prophylaxis)
- Reduction of HSV transmission from people with recurrent infection to uninfected individuals
- Herpes zoster (shingles): the typical dosage for treatment of herpes is 1,000mg orally three times a day for seven consecutive days. 
- Prevention of CMV disease following organ transplantation
- Prophylaxis against herpesviruses in immunocompromised patients (such as patients undergoing cancer chemotherapy)