Topic: Postherpetic Neuralgia
Subject: Medicine
When given during acute herpes zoster (varicella) infection, which one of the following drugs has been shown to reduce the incidence of postherpetic neuralgia?

A systematic review of 42 randomized, controlled trials showed that acyclovir reduced the incidence of postherpetic neuralgia at 3 months (number needed to treat = 3.2-8.0). Famciclovir was shown to reduce the duration of postherpetic pain. No conclusions could be drawn with regard to amitriptyline, narcotics, capsaicin, anticonvulsants, or percutaneous nerve stimulation. Studies examining these treatments were of fair to poor quality. Systemic corticosteroids showed no additional benefit.