Prickly heat, characterized by small red papules or blisters on the skin, often occurs during the hot summer months or in high-temperature working conditions.

Suwen. Shengqi Tongtian Lun refers to it as "fei." Fei is synonymous with prickly heat, hence it is also referred to as prickly heat in later generations, or sometimes called fei sores.

bubble_chart Pattern Analysis

1. Dampness-heat︰Sudden appearance of numerous red rashes on the skin, as small as needle tips or foxtail millet grains, with red halos around them. In severe cases, they cluster and merge into patches, accompanied by flushed skin, pricking itchiness, vexing heat without sweating, a red tongue with thin yellow or slightly greasy coating, and a soggy, rapid pulse. The characteristic features are heat predominating over dampness, red rashes with surrounding halos, and intense pricking itchiness. Treatment involves clearing heat and draining dampness using the diffusion method. Modified Skullcap Decoction and Coix Seed and Bamboo Leaf Powder can be selected, with Six-to-One Powder plus Alum applied externally.
2. Summerheat-dampness Steaming︰Numerous small blisters rapidly appear on the skin, white and shiny, resembling the size of India mustard seeds or pinheads, without surrounding redness, scattered or clustered, with no obvious subjective symptoms. The tongue texture is red or normal, with a greasy coating, and the pulse is soggy and slow. The characteristic features are dampness outweighing heat (summerheat), small blisters without surrounding redness, thin-walled blisters that are white, crystal-clear, and shiny, easily ruptured with light pressure, leaving behind thin, fine scales. Treatment focuses on resolving summerheat, dispelling dampness, and promoting diuresis, often using Clearing Summerheat Decoction or Yin Yun Decoction with modifications. For external use, Stachys Powder with borneol can be applied to the body. If small pustules appear, Indigo Powder can be dusted on the affected area.

bubble_chart Documentation

1. Waike Dacheng-Prickly Heat："Prickly heat initially appears as itchy blisters, which then turn into painful pustules. The classic text states: 'When sweat encounters wind, it gives rise to boils and prickly heat.' This condition arises from lung heat and spleen dampness, and should be treated with blood-cooling Wind-Dispersing Powder."