The source is from the branch and leaf of Baphicacanthus cusia (Nees) Bremek, or Potygonum tinctorium Ait. or Isatis tinctoria L., family Acanthaceae, Polygonaceae or Cruciferae. The fallen leaves are collected in autumn, and soaked in water until they are rotten, dredged up from water and then just right amount of lime white is put in the rotten leaves, which is fully stirred until maceration extract becomes dark red from dark green, at last the foam on the solution is dredged up, which is dried in the sun for being used.

Medicinal Properties:
Salty in flavor, cold in nature and attributive to the liver meridian.

Actions:
Clear away heat and liver-fire, and relieve toxin, cool blood and disperse maculae, and stop convulsion.

 

Application
1. It is indicated for overabundance of pathogenic heat manifested as fever, excessive thirst, or maculae and papules, and especially suitable for syndrome of heat involving yingfen and xuefen manifested as maculae.
2. For bleeding due to blood-heat manifested as haematemesis and epistaxis, it's used together with Shengdihuang ( Radix Rehmanniae), Mudanpi ( Cortex Moutan Radicis ), Baimaogen ( Rhizoma Imperatae ) and others that can clear away heat and cool blood. Since it can clear away liver-fire and phlegm-heat, for liver-fire attacking the lung resulting in hemoptysis or bloody sputum, the single Qingdai (Indigo Naturalis ) is effective but also combined with the powder of Haigeke
3. It is generally used for mumps, laryngalgia and pyocutaneous diseases.
4. It is used for convulsive epilepsy due to summer-heat and convulsion or infantile convulsion.