The source is from the root of Isatis tinctoria L., family Cruciferae. The root is dug and collected in autumn, from which silt is removed, dried in the sun and the crude is used. Medicinal Properties Bitter in flavor, cold in nature and attributive to the heart and stomach meridians. Actions Clear away heat and remove toxin, cool the blood and benefit the throat. Application It is indicated for seasonal febrile diseases with fever, sore throat, maculae and papules, swollen head due to infection, carbuncle, and sore toxin, etc.. Since its action is stronger in clearing away heat and removing toxin, it is usually used for overabundance of heat and good at removing toxn and benefiting throat as well. For exogenous wind and heat with fever, headache or onset of seasonal febrile diseases with the above syndromes, it is usually combined with Jinyinhua (Flos Lonicerae), Lianqiao ( Fructus Forsythiae ) , and Jingjie (Herba Schizonepetae), etc. ; for the treatment of swollen head due to infection with red and swollen face and head, unsmooth throat, usually combined with Xuanshen (Radix Scrophulariae), Lianqiao ( Fructus Forsythiae ), and Niubangzi (Fructus Arctii), etc., such as Puji Xiaodu Yin (Decoction). It is now often used for infectious diseases of pathogenic factors, such as encephalitis B, hepatitis, and epidemic parotitis, etc.. Usage and Dosage 10 -15 g is used in decoction for oral use. Notes Contraindicated for deficiency and cold of the spleen and stomach.
