Herpes zoster--predicting and minimizing the impact of post-herpetic neuralgia.

Herpes zoster results from reactivation of latent varicella-zoster virus in the dorsal root ganglia and is frequently associated with severe pain. Most patients suffer acute pain during the rash phase, and in many, prodromal pain or discomfort also precedes the rash. The pain of herpes zoster gradually resolves with time, but may persist after the acute disease as post-herpetic neuralgia for weeks, months or even years. Post-herpetic neuralgia, the most common complication of herpes zoster, often results in significant morbidity and healthcare resource usage. Early treatment with oral antivirals has been shown to accelerate the resolution of postherpetic neuralgia, with therapeutic effects particularly evident in the over-50 age group, where pain generally persists for longer. Progressively increasing life expectancy of the population translates to increasing numbers of cases of herpes zoster. The socio-economic gains associated with active management, including use of oral antivirals where indicated, to speed resolution of pain and post-herpetic neuralgia, readily justify additional cost.