Valacyclovir or Valtrex is an anti viral drug used to treat infections such as herpes simplex - cold sores, genital herpes, shingles.
Valacyclovir or Valtrex is the pro drug of acyclovir, meaning that in the body it is converted to the active drug acyclovir. Acyclovir interferes with viral reproduction.
In shingles Valacyclovir or Valtrex reduces the fever, lesions, and shortens the duration of the infection. It is able to shorten the pain the occurs after the shingles have 100% cleared - the post herpetic neuralgia.
Valacyclovir or Valtrex can cause nausea and headache. It also may be involved in kidney damage.
Because of the potential kidney problems, people with existing kidney damage should be careful using Valacyclovir or Valtrex.
Valacyclovir or Valtrex levels within the body can be increased by probenecid and cimetidine.
Med Letter 1996;38:3
The relevant product monographs must be regarded as the appropriate sources of prescribing information.