Herpes zoster is an infectious skin disease caused by varicella-zoster virus (VZV) and characterized by clusters of small blisters along the unilateral peripheral nerves, often accompanied by significant neuralgia. VZV has dermatophilic and neurological properties. The virus enters the bloodstream through the respiratory mucosa to form viremia, and chickenpox occurs or is an insidious infection. Later the virus is latent in the posterior root ganglion of the spinal cord or the sensory ganglion of the cranial nerve. When the body is stimulated by trauma, fatigue, malignant tumor, or post-illness weakness, the body’s resistance decreases and the latent virus is activated and travels down the sensory nerve axon to replicate in the skin cells innervated by the nerve, producing blisters. At the same time, the affected nerve becomes inflamed and necrotic, producing neuralgia. The disease occurs in adults and is more common in the spring and autumn. The typical manifestations of the disease are: 1. antecedent symptoms, i.e., mild malaise, low fever, general malaise, and poor circulation before the onset of the rash, which may be misdiagnosed as a cold. Self-perceived burning sensation or neuralgia in the affected skin, lasting 1 to 3 days. The rash may also develop without antecedent symptoms. The rash is characterized by flushed patches on the affected area, followed by corn to soybean-sized papules that appear in clusters and do not fuse, and then rapidly turn into blisters with tense, shiny walls and clarified fluid, surrounded by a red halo. The rash develops one after another. After a few days, the blisters dry up and crust over, leaving temporary light red spots or pigmentation after healing. Skin distribution The lesions are arranged in a band along a peripheral nerve, mostly on one side of the body, usually not exceeding the midline. The most common sites are the waist, neck and face in order of preference. Neuralgia is one of the characteristics of the disease and can occur before the onset of the disease or along with the rash, and is often more intense in elderly patients. The duration of the disease is usually 2 to 3 weeks, and 3 to 4 weeks in the elderly. Neuralgia associated with herpes zoster mostly disappears after the lesions have completely subsided or within 1 month of onset. If the neuralgia persists for more than 1 month after the lesions have completely resolved, it is called postherpetic neuralgia. The clinical manifestations are spontaneous knife-like or lightning-like attacks of pain or persistent burning pain mainly, abnormal pain and nociceptive hyperalgesia, and most patients have severe and unbearable pain levels. Postherpetic neuralgia is one of the intractable pain disorders that plague the middle-aged and elderly population, with a duration ranging from 1-2 years to more than 10 years in the longest cases. The disease is self-limiting, and the principles of treatment are antiviral, analgesic, anti-inflammatory, and prevention of complications.