Dang Shen (Szechwon Tangshen Root)

Name

Dang Shen (Radix Codonopsis), recorded in Zeng Ding Ben Cao Bei Yao.

Source and quality

Plant

The root of the perennial Codonopsis pilosula (Franch.) Nannf., C. pilosula Nannf. var. modesta (Nannf.) L. T. Shen, or C. tangshen Oliv., family Campanulaceae.

Where it is grown

Shanxi, Shaanxi and Gansu provinces.

Harvest

Lifted in autumn.

Smell and taste

Distinctively fragrant, with a strong smell and a slightly sweet flavor.

Better grade

Stout root, soft and moist, and chewed without leaving dregs.

Processing

Cut into thick slices; used raw.

Nature and action

Sweet and neutral; enters the lung and spleen channels. Invigorates lung qi and spleen qi, nourishes the blood, and promotes the generation of body fluid.

When it is used

Lung and spleen qi deficiency

Dang Shen resembles Ren Shen but is weaker, and it invigorates lung and spleen qi without being either dry or greasy. It is therefore used for the syndromes caused by deficiency of spleen and lung qi.

For a mild spleen-lung qi deficiency it substitutes for Ren Shen in formulas such as Si Jun Zi Tang, Bu Zhong Yi Qi Tang and Gui Pi Tang. For weakness of constitution, lassitude, poor appetite and loose stool from spleen qi deficiency, it is combined with herbs that tonify the spleen and remove dampness, such as Bai Zhu and Fu Ling.

For anal prolapse, prolonged diarrhea or prolapse of internal organs caused by collapse of the middle qi from spleen qi deficiency, it is combined with herbs that tonify qi and raise yang, such as Huang Qi and Sheng Ma. For cold pain in the stomach and abdomen, or vomiting and diarrhea, from spleen qi deficiency with a cold pathogen, it is combined with herbs that tonify the spleen and warm the middle, such as Bai Zhu and Gan Jiang.

For chronic bleeding from spleen qi deficiency failing to hold the blood in the vessels, it can be used alone in a large dose to tonify qi and hold the blood in place, or combined with other qi-tonifying and bleeding-stopping herbs to strengthen the effect. For shortness of breath, cough and wheezing, and difficulty speaking with a faint, low voice from lung qi insufficiency, it is combined with herbs that tonify the lung and relieve asthma, such as Huang Qi, Wu Wei Zi and Ge Jie.

Blood deficiency, or deficiency of both qi and blood

It can tonify both qi and blood, though it is weaker than Ren Shen and is commonly used as a substitute for it. It is used for blood deficiency caused by insufficient qi production, and for combined qi and blood deficiency of the same origin. These patterns come with a pale or sallow complexion, lassitude, vertigo and palpitations. It is used together with herbs that nourish yin and generate body fluid, such as Mai Dong and Wu Wei Zi.

Dose

Decoction 10~30 g.