Epidural block is very useful in the treatment of herpetic pain and post herpetic neuralgia. However, in the elderly patients with cardiac disease or diabetes mellitus, severe cardiovascular changes may occur by epidural block. Epidural block caused severe hypotension in two elderly patients with herpetic pain and post herpetic neuralgia who had diabetes mellitus or hypertension. Continuous thoracic sympathetic ganglion block with local anesthetics through a placed catheter reduced their pain and caused almost no changes in cardiovascular system.