Herpes zoster is a viral skin disease characterized by clusters of herpes and neuralgia along the nerves caused by varicella-zoster virus infection. Neuralgia is an important feature of the disease, and some patients continue to have neuralgia at the invaded site even after the herpes has subsided, which may last for months or even years, called postherpetic neuralgia (PHN). It is the most common complication after herpes zoster. The cause is varicella-zoster virus, which causes chickenpox when first infected in children, and after recovery from chickenpox a small amount of virus is latent in the dorsal root ganglia of the spinal cord or in the sensory ganglia of the cranial nerves (e.g., trigeminal ganglia, geniculate ganglia); in a few patients the virus reactivates in adulthood and spreads along the sensory areas innervated by the nerves and causes herpes zoster. Its incidence is age-related, i.e., the older the patient is, the more likely he or she is to develop postherpetic neuralgia, so it is more frequent in the elderly. It is also associated with immunity. The susceptible population for postherpetic neuralgia is mainly the elderly and immunocompromised patients, commonly in: patients with malignant tumors (especially lymphoma); patients on immunosuppressive therapy (radiotherapy, chemotherapy, hormone use, organ transplantation, etc.); patients with chronic diseases (liver and kidney insufficiency, hypoproteinemia, etc.); HIV infection; and people over 60 years old. It has been reported that for people over 50 years of age, PHN occurs in about 10-20% after herpes zoster. Pain characteristics The onset of pain in PHN is earlier than herpes, usually appearing 3-5 days before herpes; the area of pain distribution is most common in the chest dermatome, followed by the head, face and abdominal dermatome; most patients with PHN have persistent background pain, on top of which eruptive pain occurs; the pain is burning-like, The pain is burning, aching, banding or anthroposis-like, mostly moderate to severe, often triggered by touching the painful area, temperature change, emotional changes, etc. Treatment of herpes zoster neuralgia From most of the domestic and international literature, there are four main areas: oral medications, local medications, nerve blocks, and surgery. On the whole, the treatment effect is poor. Oral medications mainly include three major categories: anticonvulsants (gabapentin, pregabalin, carbamazepine, etc.); antidepressants (tricyclic antidepressants, selective 5hydroxytryptamine uptake inhibitors, etc.); and opioids (tramadol, morphine, oxycodone controlled or extended release dosage forms, etc.). It is important to note that tramadol should not be combined with tricyclic antidepressants. Topical treatment is usually administered early in the post-blister pain and consists of: lidocaine patches (usually containing 5% lidocaine), capsaicin, transcutaneous electrical nerve stimulation . Depending on the site of pain, the appropriate area of nerve block can be selected, which usually requires multiple sessions. The main methods are: thoracolumbar paravertebral nerve root block, supraorbital nerve block, thoracic sympathetic ganglion block, stellate ganglion block, and continuous epidural block of the spinal cord. The purpose of surgery is to block or modulate pain transmission or to administer drugs to the central nervous system to control pain, mainly including: spinal cord electrical stimulation, spinal cord dorsal root medullary incision, and continuous drug pumping in the subarachnoid space. Evidence for the treatment of PHN Class A evidence: antiviral therapy has a preventive effect; anticonvulsants, antidepressants, opioids, and lidocaine patches have a therapeutic effect. There is no evidence yet that SCS is effective. Currently, we use a multimodal stepwise treatment approach, and many older adults with even 1-2 years of posterior neuralgia can have significant improvement and reduction in symptoms.