One hundred twenty-nine patients with acute shingles or postherpetic neuralgia (PHN) were studied. The McGill Pain Questionnaire distinguishes qualitatively between shingles and PHN and shows that PHN pain is not only more severe than the pain of shigles, but is more severe than most nocigenic pains due to damage of nonneural tissue. Multiple and repeated sympathetic and somatic nerve block relieves the pain of acute shingles and appears to be of value in preventing the subsequent occurrence of PHN. In the absence of such prophylaxis, the most effective treatment of PHN appears to be prolonged therapy with anticonvulsants and tricyclics. It is emphasized that early treatment of acute shingles by sympathetic blockade and perhaps also local infiltration should be instituted at the first opportunity in order to prevent the later development of PHN, which is much harder to treat. If PHN does occur, time should not be wasted in attempting to obtain relief with conventional analgesics, which are ineffective in this as in other neurogenic pains arising from nervous system dysfunction.