The source is from the root and rhizome of Cgnanchum atratum Bunge or C. versicolor Bunge, family Asclepiadaceae. The medicinal material is produced in all parts of China, dug and collected in autumn, dried in the sun and used alone.

Medicinal Properties:
Bitter and salty in flavor and cold in nature and attributive to the lung, liver and stomach meridians.

Actions:
Clear away heat, cool the blood, promote diuresis and relieve stranguria, eliminate toxin to treat sore.

 

Application
1. It is indicated for the late stage of seasonal febrile diseases with the pathogenic factors involving yingfen and xuefen with prolonged fever and fever due to yin-deficiency. It can clear away both sthenia and asthenia heat. For seasonal febrile diseases involving yingfen and xuefen, fever being severe at night or maculae and papules, it can be used together with Shengdihuang (Radix Rehmanniae), Mudanpi ( Cortex Moutan Radicis), etc.; for prolonged fever or fever due to yin deficiency, and hectic fever due to yin deficiency, usually combined with Shengdihuang (Radix  Rehmanniae), Zhimu ( Rhizoma Anemarrhenae ) , and Qinghao ( Herba Artemisiae Annuae), etc.
2. For stranguria of heat type and stranguria complicated by hematuria, it is usually combined with Mutong (Caulis Akebiae), Huashi (Talcum ), and Cheqianzi ( Semen Plantaginis), etc..

3. For overabundance of toxin due to blood-heat manifested as swollen and painful carbuncle, swollen-sore throat, snake-bite poisoning, used both internally and externally or together with other herbs that clear away heat and eliminate toxic materials.
In addition, it can also be used for cough due to lung- heat or exogenous fever due to yin-deficiency.

Usage and Dosage:
4 - 9 g is used in decoction for oral use.

Notes:
Contraindicated for deficiency and cold of the spleen and stomach with poor appetite and loose stool.v