Peripheral nerves can be damaged by trauma, surgery, scar tissue, or illness and therefore cause pain. Peripheral nerve block is performed to isolate and diagnose the source of pain and to provide therapeutic relief by reducing the inflammation. The area to be injected is prepped with alcohol. A small needle is inserted into each site and the medication injected onto the nerves. The injection is contained with local anesthetic and sometimes a steroid (anti-inflammatory medication). The degree and duration of pain relief varies from person to person, and additional injections may be needed. There are no guarantees injections will help your pain; and in rare cases, pain may actually be made worse.