The people say that toothache is not a disease, but a pain that kills! In my words, post-herpetic neuralgia is a disease that kills people when it hurts. Without timely and effective treatment, it can become a serious threat to the physical and mental health of the elderly! The traditional belief is that pain is only a symptom of a disease, not an independent disease. For example, back and leg pain is often caused by degenerative lesions of the lumbar spine, so most patients will go to orthopedic injury; for example, advanced cancer pain, because malignant tumors destroy the body tissues causing severe pain, patients and their families will try everything to treat this tumor, often neglecting the control of pain, and as a result, patients’ quality of life is seriously reduced because of pain during their limited survival!