Epidemiology and management of postherpetic neuralgia.

Herpes zoster occurs rarely in immunocompetent children and infrequently in immunocompetent young adults. However, its incidence increases with age, particularly after age 50. Reactivation of varicella-zoster virus (VZV) is characterized by a rash and is generally accompanied by considerable pain, dysesthesias, and skin hypersensitivity. Chronic pain that is sometimes experienced after the rash has healed is referred to as postherpetic neuralgia (PHN), the most common complication of herpes zoster. Postherpetic neuralgia is often severe and, unfortunately, refractory to most forms of treatment. The incidence of PHN also increases dramatically with increased age. More than 50% of zoster patients over 60 years old will develop PHN, which may persist for months and even years. Thus, established PHN is difficult to manage, often causing serious morbidity, depression, and high costs in terms of consumption of healthcare resources. Currently, early antiviral treatment with famciclovir has shown promise of reducing the duration of PHN.