Postherpetic neuralgia is a painful condition that persists in the affected area for more than 1 month after the herpes lesions have subsided. After recovery from varicella, a small amount of the virus is latent in the dorsal root ganglion of the spinal cord or in the sensory ganglia of the cranial nerves (e.g., trigeminal ganglion, geniculate ganglion), and under certain conditions the virus is reactivated, first destroying the nerve, causing hemorrhage and necrosis in the latent ganglion, sensitizing the nerve trunk and peripheral nerves, and causing severe pain. The virus spreads along the innervated areas causing herpes zoster. In some patients, the pain caused by nerve damage persists after the skin injury has healed and becomes postherpetic neuralgia. What kind of patients are prone to postherpetic neuralgia when they have shingles? The following should be on high alert: Elderly people, people aged >50 years or older. Patients who present with fever. Patients with severe pain levels. Patients who fail to take regular antiviral medications. Immunocompromised patients. Patients with immunosuppressive therapy (radiotherapy, chemotherapy, use of hormones, organ transplantation, etc.). Patients with malignant tumors. Patients with chronic diseases (liver disease, diabetes, AIDS, etc.). The above patients who have shingles are recommended to apply antiviral drugs in the early stage, in addition to the treatment of neuralgia, which must be paid attention to. Various drugs and nerve block methods should be used as early as possible for analgesia and prevention of post-herpetic neuralgia.