One of the most important aspects to the treatment of chemosensory disorders, is the identification of the underlying cause of the chemosensory symptoms or the chemosensory symptom generator. For many forms of chemosensory symptoms, especially in taste dysfunction, there can be significant overlap or similarity in the symptoms produced by the chemosensory symptom generators. For example, dysgeusia (distorted ability to taste) can originate from at least several different sources, including chorda tympany branch of the facial nerve (innervating taste buds on the front of the tongue), lingual branch of the glossopharyngeal nerve (innervating taste buds at the back of the tongue), and nerve endings of the trigeminal nerve that project into the papillae and other oral mucosa surfaces (where they signal sensations of touch, pain, and temperature – other components of flavor – e.g., the fizziness of carbonated drinks and the warmth of coffee). The treatment for each of these nerves can be quite different, so it is very important to identify the chemosensory symptom generator. A Diagnostic Nerve Block is used to confirm the location of the chemosensory symptom generator(s) and the nerve(s) carrying impulses from these structures. Once identified, the chemosensory symptom generator can be treated with a variety of interventional treatments including repeated nerve blocks with anesthetic or other chemicals.

A patient is not sedated for a diagnostic nerve block procedure because he/she must be able to provide reliable information regarding any change in chemosensory symptoms immediately during and after the procedure. Although a diagnostic nerve block sounds like it might be painful, this technique is very well tolerated by adult patients of all ages.