After it is somehow triggered to reemerge, the virus grows along a nerve, damaging it and showing up on the skin surface as a painful rash of small, crusting blisters. In many cases, the rash is preceded by a few days of itching or painful skin in the affected area. The rash most often appears on a band of skin wrapping around the ribs on one side of the body. Less often it affects a strip on one side of the neck or face. Acute herpes zoster and postherpetic neuralgia are two very different diseases, says Galer.
Herpes zoster is an acute pain problem that typically lasts no more than a month.
Postherpetic neuralgia is a chronic pain problem that can last from several months to many years. According to Galer, who is also an attending physician at the UW Multidisciplinary Pain Center, the use of narcotics or even in some cases nerve blocks to treat acute herpes zoster pain is appropriate, but those methods don't prevent pain that persists after the rash heals, and they aren't appropriate for treating postherpetic neuralgia. Likewise, acyclovir, an anti-viral, which can speed healing of the rash and decrease the pain associated with it, doesn't seem to prevent postherpetic neuralgia. Galer points out that acyclovir and possibly steroids can be effective while the rash is present, but they should be discontinued by the time the rash has healed. Although many attempts have been made to develop effective pain relief treatments for postherpetic neuralgia there are no tried and true treatments that have been shown to work for all patients.