Post-Herpetic Neuralgia  Pharmacological Approaches  Interventional Approaches  Neurostimulatory Approaches  Psychological/Mind-Body Therapies Conventional Approaches Interventional Approaches Nerve blocks use drugs, chemical agents or surgical techniques to interrupt the relay of pain messages between specific areas of the body and the brain. Various techniques and agents can be used. While nerve blocks may be effective in relieving pain during the acute phase of shingles, they do not appear to provide long term relief of PHN (Kanazi, 2000) Regional sympathetic block (such as a stellate ganglion block for pain in the head or neck, arm, or upper chest) has been used in the treatment of PHN. The evidence that the approach works is not conclusive, however, because none of the studies were carefully controlled. Although areview of 77 cases of PHN suggested good efficacy of stellate block in those with pain of less than one year's duration (Milligan, 1985), the true effectiveness of sympathetic block in PHN is unclear and the technique is usually tried only if medications prove ineffective.