Reduction of postherpetic neuralgia in herpes zoster

Persons 50 years of age and older are not only at increased risk of developing herpes zoster, they are also more likely to suffer the long-term morbidity of postherpetic neuralgia (PHN). PHN is pain persisting after the rash of herpes zoster has healed. PHN affects at least 40% of all herpes zoster patients over age 50 and over 75% of herpes zoster patients over age 75; PHN is the single most common neurologic condition in elderly patients. The objective of this review is to evaluate interventions that may reduce or even eliminate PHN. No single therapy has been consistently effective for PHN. The most effective approach appears to be with the use of antiviral therapy early in the course of herpes zoster. The goals of ongoing studies in herpes zoster are to develop interventions that will further reduce the symptoms of PHN and/or to eliminate PHN by prophylaxis using the varicella vaccine. Reduction of PHN can best be achieved with the use of antiviral medication early in the course of herpes zoster; other classes of drugs are minimally effective in treating established PHN. Widespread use of the varicella vaccine may lead to secondary reductions in PHN in the distant future.