Pharmacologic management of herpes zoster and postherpetic neuralgia.

Herpes zoster is an infection caused by reactivation of dormant varicella-zoster virus. The acute course of herpes zoster is generally benign; however, some patients will experience postherpetic neuralgia characterized by severe, relentless, and at times disabling pain that is often refractory to treatment. While herpes zoster responds to acyclovir, cost-benefit considerations limit the drug's usefulness to only a select group. Postherpetic neuralgia requires a holistic approach, including pharmacologic therapy using several different classes of drugs.