Sphenopalatine block is a nontraditional treatment used for chronic pain. It's used sometimes in conditions like fibromyalgia, headache, and myofascial pain syndrome. Usually the patient has been treated without success with drugs, physical therapy, and acupuncture.

The sphenopalatine block puts a local anesthetic (lidocaine, tetracaine) on the sphenopalatine ganglion (SPG). The SPG is a group of nerve cells outside the nervous system. Pain messages can't get through to the brain when blocked by this numbing agent.

Reports on the use of this type of block suggest it gives partial relief of pain. Patients may get up to 50 percent pain reduction.

A recent study at the Robert Wood Johnson Medical School in New Jersey reported use of sphenopalatine block in two cases. Both patients were women who had an accident and were left with leg pain diagnosed as complex regional pain syndrome. They both got 50 percent relief of their painful symptoms.