Radix Puerariae
The Processing of Radix Puerariae
Origin
The root of the perennial Liane Pueraria Lobata (wild.) Ohwi. or Pueraria thomsonii Benth. which belongs to the family of leguminosae.
Location
Pueraria lobata (wild.) Ohwi. is mainly produced in Hunan, Henan, Guangdong provinces of China, while Pueraria thomsonii Benth. is cultivated artificially, mainly produced in Guangxi and Guangdong provinces of China.
Harvest
Collected in autumn or winter.
The real smell and taste
Odorless, a little bit sweet.
Best quality
Big, firm, white one with profuse powder inside but less fiber.
Processing
Unprocessed or roasted.
The Effect of Radix Puerariae
Property
Sweet, pungent, cool; lung, spleen and stomach meridians entered.
Actions
Release exterior and cure fever, promote eruption, promote the production of fluid and relieve thirst, ascend yang to check diarrhea.
Indications
A. High fever of exterior syndromes
This herb has the action of expelling the external wind pathogen and reducing fever by diaphoresis. It can be used for high fever of exterior syndromes due to external contraction either by wind-cold or wind-heat. For wind-cold exterior syndrome, it is used with herbs having efficacy of dispelling wind-cold, such as Ma Huang, Qiang Huo, Fang Feng and so on. For wind-heat exterior syndrome, it can be used with wind-heat-dispersing herbs or heat-clearing herbs such as Bo He, Jin Yin Hua and so on. Because this herb can both dispel external wind and clear internal heat induced by pathogen stagnation, it is usually used to treat exterior syndromes, accumulated pathogens transforming into fire, invading the internal organs, which manifested as fever aggravated, aversion to cold, dryness of the nose and pain in eyes and slight thirst. For example, in the book of Shang Han Liu Shu, the famous decoction named Chai Ge Jie Ji Tang, Ge Gen is used with Chai Hu, Bai Zhi, Qiang Huo, and Huang Qin. This herb also has the action of relieving the stiffness and pain of shoulder and neck which is caused by stagnation of external pathogen, dysfunction of meridian qi and malnutrition of muscles and meridians, and this kind of symptom is mainly seen as wind-cold exterior syndrome. For the exterior excess accompanied by no sweating, it is often used with Ma Huang Tang, such as Ge Gen Tang from the book of Shang Han Lun; for the exterior deficiency accompanied by sweating, it is usually combined with Gui Zhi Tang, just as Gui Zhi Jia Ge Gen Tang from the book of Shang Han Lun.
B. Unsmooth eruption of measures that still at the beginning stage
This herb can both expel the external pathogens and promote the eruption, It is mainly used for the measles first come without adequate eruption. Because of the invasion of wind-heat, it is usually used with with Niu Bang Zi and Sheng Ma which can dispel wind-heat, relieve toxicity, and promote eruption, such as Sheng Ma Ge Gen Tang from the book of Yan Shi Xiao Er Fang Lun (Discussion on Pediatric Prescriptions of Yan Jizhong), Ge Gen and Sheng Ma are mutually reinforced.
C. Thirst due to warm diseases and diabetes
This herb has the effect of promoting the production of fluid and relieving thirst. So it is mainly used for patient with restless thirst. The property of this herb is sweet and cool, so it is fit for the symptom of thirst induced by consumption of fluid due to warm diseases. For this kind of syndrome Ge Gen will be used with Zhi Mu and Shi Gao which have effect of clearing heat and eliminating the fire. For the syndrome of diabetes caused by yin deficiency converting into dryness it will be used with herbs which function as promoting the generation of fluid and tonifying the stomach, such as Tian Hua Fen, Shan Yao and so on. Also Ge Gen has the action of promoting the clear qi of spleen and stomach to ascend upward. For the diabetes caused by qi deficiency of spleen Ge Gen will be used with Ren Shen and Huang Qi, the herbs which can tonify qi so as to help the generation and transformation of body fluid.
D. Diarrhea due to spleen deficiency
This herb can promote the clear qi of spleen and stomach to flow upward. For the patient who suffer from diarrhea caused by deficiency of spleen and collapse of qi which lead to dysfunction of transportation and transformation, Ge Gen will be accompanied by herbs having action of tonifying qi and invigorating spleen, so as to lift up the clear yang and arrest diarrhea. For the patient who suffers from dysentery with fever, Ge Gen will be used together with Huang Lian, Huang Qin and so on which have actions of clearing heat, resolving dampness and detoxifying, so as to expel pathogen from exterior and relieve fever.
Dosages and Administration
Decoct 3~10 g. For relieving exterior and reducing heat of blood, it should be used unprocessed. For raising the clear yang and arresting diarrhea, it should be roasted in fresh cinders.