Objective
To assess the clinical manifestation of acute herpes zoster associated pain (AHP) and postherpetic neuralgia (PHN) and nerve block effect in AHP and PHN.

Method
We assessed twenty eight patients by physical examination and pain questionairre, and nerve block effect in thirty one patients. We injected local anesthetics and triamcinolone into nerve root or trunk in study group, and saline in control group. The effect was assessed by visual analogue scale.

Result: 1. Clinical manifestation: There was high incidence in thoracic dermatome. AHP and PHN patients expressed "sharp" pain. Pain rating index of AHP and PHN were 32.9, 33.0. 2. Nerve block effect: There was no nerve block effect in AHP (p＞0.05) and PHN (p＞0.05), but four patients of PHN patients in study group had significant pain relief, who suffered from pain during 2 month, 10 month, 6 years, 8 years.

Conclusion
AHP and PHN had variable clinical manifestation but no difference between them. There was no nerve block effect in AHP and PHN but we can consider nerve block as a additive method for pain relief of PHN because some patients responded to nerve block and there was no significant complication in nerve block.