Intractable neuralgia includes trigeminal neuralgia, postherpetic neuralgia, glossopharyngeal neuralgia, and neuralgia caused by diabetic peripheral neuropathy. The pain of neuralgia is characterized by lightning-like attacks with abnormal sensations such as pins and needles, radiating sensation, cutting sensation, insect bite sensation, and ants walking sensation. The manifestations of neuralgia are spontaneous pain, pain allergy and pain hypersensitivity. Spontaneous pain is spontaneous pain with exertion and rest; pain allergy is lightning pain that can occur with very small stimulation, such as when wearing clothes; pain hypersensitivity is nerve pain that can be caused by slight touching of the skin.