Valacyclovir and Postherpetic Neuralgia

Abstract

Objective: To describe the role of valacyclovir in the treatment of acute herpes zoster pain and its effect in postherpetic neuralgia. Data Sources: A literature search was conducted on MEDLINE (1980–October 2003). Search terms included valacyclovir, postherpetic neuralgia, treatment, acyclovir, and valacyclovir. Study Selection and Data Extraction: Articles describing use of valacyclovir in the treatment of herpes zoster, with focus upon alleviation of acute zoster pain and postherpetic neuralgia, and articles describing use of valacyclovir for this indication in comparison with other antivirals were evaluated. Data Synthesis: Four studies discussing the use of valacyclovir in the treatment of herpes zoster with focus on herpetic pain and postherpetic neuralgia were identified. All of these studies reported that valacyclovir is an effective treatment for herpes zoster and alleviates associated pain significantly faster than acyclovir, presumably due to its greater bioavailability. Valacyclovir likely results in a higher adherence rate than acyclovir because it is dosed 3 versus 5 times daily. Interestingly, the severity of pain was not significantly different between the 2 treatments, only the duration. Finally, one study showed that valacyclovir is equally as effective as famciclovir in alleviating pain associated with herpes zoster. Conclusions: Valacyclovir 1 g given orally 3 times a day for 7 days is effective in the treatment of herpes zoster. It is superior to acyclovir 800 mg given orally 5 times a day for 7 days and equivalent to famciclovir 500 mg given orally 3 times a day for 7 days in alleviating acute zoster pain and postherpetic neuralgia.