What is a Nerve Block? A Nerve Block is a procedure performed by a pain management physician to anesthetize or numb a particular nerve in the body to treat certain forms of chronic pain. A Nerve Block involves the injection of a local anesthetic like Lidocaine or Bupivicaine onto a target nerve or group of nerves. An example of a therapeutic nerve block used to treat chronic pain is the Stellate Ganglion Block, performed in the front of the neck to treat Complex Regional Pain Syndrome (CRPS or RSD).