its a fine thing to speak about tn, the pain,the meds,,,and to seek some kind of comfort in forums,,,but far better to question doctors expertise,,,when in fact ,we, are the real experts,,when you step outside their office,you,and your pain are quickly forgoten,,the one and only thing that causes tn,,is change in brain chemistry,,after all,,,its the brain that interprets the nerve singnal,,but since all tn has the same symptoms,more or less,,,it must surly have one cause..and what does tegretol do,,,it changes brain chemistry,,,