In TCM, virus is activated to cause the attacked ganglion inflamed and necrotic, leading to neuralgia. Virus migrates along the peripheral nerve fiber to the skin to present segmental herpes.This disease gives a life-long immune and recurs occasionally. This disease belongs to the category of "Snake Boil" and "Fire Blisters along the Lumbus" in Chinese medicine. The onset is often caused by internal pathogenic dampness due to internal accumulation of dampness and heat in the liver meridian or failure of the spleen in transportation and invasion of exogenous toxins and transmission of pathogenic dampness and heat to the skin along the meridian, and also by obstruction in the meridians. If the anti-pathogenic ability becomes deficient and qi and blood are stagnant, pain can last continuously.