Valtrex contains Valaciclovir is used for treating shingles (herpes zoster), cold sores (fever blisters or herpes labialis), and treating or suppressing genital herpes in patients with normal immune systems. Valaciclovir Valtrex is also used to suppress genital herpes in patients with HIV infection. Valtrex medication is not a cure for the herpes virus but helps to reduce the infection and the pain associated with them. Generic Valtrex Valaciclovir helps to slow down the spread of the symptoms, giving your bodies natural defenses a chance to fight off the infection.slows the growth and spread of the herpes virus so that the body can fight off the infection.