Trigeminal neuralgia can be divided into two categories: primary trigeminal neuralgia and secondary trigeminal neuralgia. Primary trigeminal neuralgia is more common and refers to trigeminal neuralgia in which the exact cause cannot be found. Secondary trigeminal neuralgia: mostly refers to trigeminal neuralgia caused by tumor compression. This type differs from the primary one in that the pain is often persistent and signs of lesions in the adjacent structures of the trigeminal nerve can be detected. The diagnosis of trigeminal neuralgia is generally easy, based on the clinical manifestations of the patient, and generally no special auxiliary examinations are needed, but when secondary trigeminal neuralgia is suspected, targeted examinations should be performed. The following are the characteristics of primary trigeminal neuralgia: 1. The site of pain is the distribution area of the trigeminal nerve or one of its branches. The site of this kind of severe pain is usually in the first branch: forehead, upper lid, eye and nose; the second branch: upper lip, lower lid, paranasal, maxillary, upper teeth and gums; the third branch: lower lip, preauricular, frontal, lower teeth and their gums and tongue. 2, mostly sudden onset of paroxysmal severe pain, when not onset of the vast majority of patients completely painless, only a very small number of patients still have mild pain. The painful attacks come suddenly and stop suddenly. In some patients, the first attack is a very severe pain; in some patients, the attack is mild at the beginning, and then gradually worsens. When the disease attacks, patients mostly complain of “Huo Huo” jumping pain, some say like a knife cut, burning pain, forcing patients to rub the face, often swollen skin rubbing broken, some will be eyebrows and beard rubbed out, some are frequent cries, or tight pressure on the pain, or open wide mouth afraid to close. At the same time, the affected side of tears, saliva and nasal fluid. The pain can come on day and night, and the number can range from tens to hundreds of times. Some patients get up from sitting or roll around on the floor when they have an attack, and then the pain stops suddenly after a few minutes and they sit down peacefully. A small number of patients do not have such severe pain, but episodes of “numbness”. 3, most patients have “trigger points”, that is, trigger points, stimulation of these points can cause pain attacks, but the attack has just passed, then stimulate the “trigger points” will not cause attacks. Common trigger points are as follows: at the eyebrows, eyes, next to the nose, below the upper corners of the mouth, around the teeth and tongue. Touching these places can cause a seizure; however, just after the seizure is over, touching these points will no longer cause a seizure. Most of the “trigger points” are in the same nerve branch. 4, More than 95% of patients with trigeminal neuralgia are unilateral. 5.The pain attacks are not combined with nausea and vomiting. 6.The general analgesic drugs are completely ineffective for this disease. 7.The course of the disease is long and the episodes of severe pain can last for many years, and in some patients the course of the disease can last for decades. A small number of patients can have a large interval, which can be months or years without attacks. Others may have episodes for ten years or decades, and the pain may stop in old age. 8, not combined with loss of sensation in the head and face, muscle paralysis or other symptoms of cerebral nerve paralysis, such as diplopia, facial palsy, etc.. Individual patients may have hyperalgesia or hypersensitivity to pain on the affected side, or weakness in chewing.