Stellate Ganglion injections are a common method of treatment for Complex Regional Pain Syndrome (CRPS) and shingles that affect the head, face, neck or arms. Stellate Ganglion injections can be used to either diagnose or treat pain. The Stellate Ganglion injection blocks the sympathetic nerves that are located on either side of the voice box in the neck. The Stellate Ganglion injection may decrease swelling, pain and sweating in the upper extremities. Although uncommon, risks may include infection, bleeding, allergic reaction to the medication and nerve damage.