Radix Sophorae Tonkinensis (Shandougen)

Naming
Shan Dou Gen (Radix Sophorae Tonkinensis)-Kai Bao Ben Cao (Materia Medica in Kai-Bao Reign)

Origin
The root and rhizoma of Sophora tonkinensis Gapnep. of family Leguminosae.

Location
Mainly in Guangxi, Guangdong, Jiangxi, Guizhou provinces of China.

Harvest
Collected at anytime, but mainly dug out in autumn. It is also called Guang Dou Gen.

The actual smell and taste
Bean-like smell, extremely bitter taste.

Best quality
Thick and big rhizome, hard quality without fibrous root.

Processing
Sliced, and unprocessed.

Property
Bitter, cold; toxic; lung and stomach meridians entered.

Actions
Clear heat and remove toxicity, alleviate sore throat and relieve swelling.

Indications
A. Swollen and sore throat
With the much stronger properties of bitter cold, it excels in clearing heat and removing toxicity to further alleviate sore throat and relieve swelling and pain. Being regarded as an essential herb for treating heat-toxicity accumulation, and swollen and sore throat, it can be used singly as gargle or in decoction, or slow swallowed with vinegar. For excessive heat-toxicity, it should be combined with herbs for clearing heat-toxicity from lung and stomach such as Rhizorna Cimicifugae (Shengma), Radix et Rhizoma Rhei (Dahuang), etc., as in Shan Dou Gen Wan from Ren Zhai Zhi Zhi Fang. For fettering exterior by wind-heat accompanied, it can be combined with wind-heat-dispersing herbs, for example in Qing Liang San from Wan Bing Hui Chun, Fructus Forsythiae (Lianqiao) are used in combination.

For yin deficiency with effulgent fire accompanied, it can be combined with yin-nourishing and fire-reducing herbs such as Xuan Shen, Mai Dong, etc. , as in Shan Dou Gen Tang from Ci You Xin Shu (A New Book of Benevolent Pediatrics).

B. Abscess with swelling due to heat-toxicity
With the actions of clearing heat and removing toxicity, relieving swelling and dissipating nodulation, it is also indicated for syndrome of excessive heat-toxicity manifested as swollen and painful gum, hemorrhoid with swollen pain, sores and abscess, and venomous insect stings. It can be decocted singly for topical soaking and washing, or pounded for topical smearing with juice, or combined with corresponding heat-clearing herbs for oral administration according to syndrome differentiation.

In addition, for it has certain actions of clearing lung-heat and eliminating damp-heat, it can also be used in treating cough due to lung-heat and jaundice due to damp-heat.

Dosage and Administrations
Decoct 3～6 g. Proper dosage is for topical application.

Cautions
It is extremely bitter and cold, and poisonous; overdosage should be avoided since that may easily cause nausea, vomiting, dizziness, headache, diarrhea, and abdominal pain, weakness of four extremities, palpitation, and oppression in chest, even deadly cold hands and feet, spasm, and so on.