Twenty patients with acute herpes zoster participated in a double-blind placebo-controlled study using sympathetic nerve blocks. Ten patients received sympathetic nerve blocks using a local anesthetic and 10 received a placebo. The local anesthetic was effective in resolving acute herpetic neuralgia in 90% of the patients while the placebo was effective in 20%. This difference is significant at thep< 0.01 level. While the exact mechanism of action of the sympathetic blockade in relieving zoster pain is not understood, the immediate relief afforded by sympathetic blocks is, however, gratifying and favors its use when available.