Treatment of herpes zoster and postherpetic neuralgia.

Herpes zoster results from reactivation of latent varicella-zoster virus. It is most common in elderly patients and immunosuppressed patients, especially those with human immunodeficiency virus (HIV) infection. Zoster is often the earliest indicator of HIV infection. The acute course of herpes zoster is generally benign, but systemic complications may be fatal. Postherpetic neuralgia is the major chronic complication and is a difficult management problem. High-dose acyclovir (800 mg orally five times daily) has recently been approved for treatment of herpes zoster and, if started early, decreases the duration and severity of symptoms. In the prevention of postherpetic neuralgia, acyclovir does not appear to be effective, and the efficacy of steroids is questionable. The best therapy currently available for postherpetic neuralgia is amitriptyline, topical capsaicin and transcutaneous electrical stimulation.