Doctors say that trigeminal neuralgia is caused by a disruption to the nerve’s function, which may have developed from a friction between a blood vessel and the trigeminal nerve. Patient complaints of excruciating pain in one half of the face or segments of one side of the face. Pain starts suddenly and described typically by patients as “shock like”. It can be triggered by touching some trigger points in the face. Even simple activities like brushing teeth, talking, smiling, chewing food or cold breeze over the face can trigger this worst form of pain.