Hi, The below is a reply from Grace to a similar question. I could not attach the post so i cut and pasted it. Hope its helps.
"Valtrex is an acyclovir prodrug. What this basically means is that you swallow valtrex and your body converts it into acyclovir inside your body. Because you get more of the active medication in your body that way - you don't have to take it as often. The advantage of valtrex is - less pills to remember to take so a greater chance of actually taking them. There isn't any other real difference between them."
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