Although most traditional dermatology texts mention Damp-Heat and Wind as the major pathogens in acute eczema, clinical experience has shown that there is generally also some degree of Heat Toxin as evidenced by the intensity of the acute stage symptoms, deep red or purple colour around the vesicles and turbid fluid or pus within the vesicles. Clinically, a better response is obtained when formulas for acute eczema contain some herbs that clear Heat Toxin, e.g. Smilax rhizome (tu fu ling) and Lonicera flower (jin yin hua).

This formula is loosely based on Long Dan Xie Gan Tang (Gentiana Formula) and Xiao Feng San (Dangui & Arctium Formula). The herbs from these formulas that dispel the pathogens from the skin are:

• Long Dan Xie Gan Tang (Gentiana Formula): Gardenia fruit (shan zhi zi), Plantago herb (che qian cao), Scutellaria root (huang qin) ‐ clear Damp-Heat
• Xiao Feng San (Dangui & Arctium Formula): Schizonepeta herb flowering top (jing jie), Sophora root (ku shen) ‐ dispel Wind and Damp and alleviate itching.

Note that some skilful substitutions have been made within the treatment principles of this formula: Angelica dahurica root (bai zhi) is paired with Schizonepeta herb flowering top (jing jie) instead of Saposhnikovia root (fang feng) as it has a stronger action on the skin. Stephania root (han fang ji) is used instead of Clematis or Akebia (mu tong) because the former, being acrid (pungent) has an action on the Exterior, i.e. it disperses Wind and Damp from the skin.

Additional herbs are included to enhance the formula’s main actions:
Bassia fruit (di fu zi), Dictamnus stem bark (bai xian pi) and Cynanchum root (xu chang qing) have strong antipruritic actions and work synergistically with Sophora root (ku shen). Finally, the following herbs have demonstrated anti-allergic actions: Scutellaria root (huang qin), Stephania root (han fang ji), Sophora root (ku shen) and Glycyrrhiza root (gan cao).

• Traditionally used in Chinese medicine to dry dampness in Damp-Heat pattern
• Traditionally used in Chinese medicine to remove Heat toxin
• Traditionally used in Chinese medicine to extinguish exogenous wind of exterior excess pattern