Radix Puerariae
- Name
- Origin
- Where Does It Grow?
- Nature and Flavor
- Identified Active Components / Major Chemical Constituents
- Drug Actions in TCM
- Traditional Uses in TCM
- Pharmacological Actions
- Toxicology
- Administration and Dosage
- Adverse Effect, Side Effects and Cautions
- References
Name
Latin Name: Radix Puerariae
Common Name: Kudzu root
Scientific Name: Pueraria lobata (Willd.) Ohwi / Pueraria thomsonii Benth.
Chinese Name: 葛根
Pinyin Name: ge gen
Origin
The dry root of Pueraria lobata (Willd.) Ohwi / Pueraria thomsonii Benth., a perennial deciduous vine of the Leguminosae family. The cane, leaf, flower bud and seed are also used medicinally. 1,2
Where Does It Grow?
Kudzu root is widely produced in China. Pueraria lobata (Willd.) Ohwi is mainly produced from provinces like Hunan, Henan, Guangdong, Zhejiang, and Sichuan. Pueraria thomsonii Benth. is mainly cultivated from Guangxi and Guangdong, other districts like Sichuan and Yunan also cultivated.1,2
Nature and Flavor
Kudzu root is cool in nature, sweet and pungent in flavor, and mainly manifests its therapeutic actions in the spleen, stomach, lung and bladder meridians.3,6
Identified Active Components / Major Chemical Constituents
Kudzu root contains many kinds of isoflavones, triterpenes and saponins. It also has rich starch, alkaloids, β-sitosterol, daucosterol, coumarin and other phenol compounds.1,5,6
The root of Pueraria lobata (Willd.) Ohwi contains isoflavones such as puerarin, daidzein, daidzin, 3’-hydroxypuerarin, 3’-methoxypuerarin, biochanin A, genistein, formononetin, tectorigenin, 7,4-di-O-methyltectorigenin, puerarinxyloside (PG-2), and 4’-O-glucosylpuerarin(PG-6); its saponins include sophoradiol, cantoniensistriol, soyasapogenols A-B, kudzusapogenols A & C, kudzusapogenol B methylester, formononetin-7-glucoside; others include puerarol, lupenone, allantoin, β-sitosteryl-β-D-glucoside, 6,7-dimethoxycoumarin, and 5-methylhydantoin.
For the root of Pueraria thomsonii Benth., the total amount of flavones is lower than the above type, but both have similar ingredients, such as daidzein, daidzin, puerarin, 4’-methoxypuerarin, daidzein-4, 7-diglucoside, and β-sitosterol.
The total amount of flavones will decline significantly if the herb becomes molded. In the Pharmacopoeia of People's Republic of China (2015 Edition) - Part I, the level of puerarin should not less than 2.4%, as the standard quality of the herb.
Drug Actions in TCM
Kudzu root expels pathogens from muscles and skin, reduces fever, promotes fluid production, quenches thirst, promotes eruption and circulation in the meridians and collaterals, and also alleviates hangover.3,6Traditional Uses in TCM
Kudzu root is often used in conditions like fever, headache, dizziness, neck stiffness, extreme thirst, diabetes, eruptive problem, diarrhea, limb weakness after stroke, chest pain and alcoholism.3,4,5
Kudzu root expels pathogens from muscles and skin to reduce fever
For cold and flu conditions that develop high fever, slight chills, headache, dry nose, and a thin yellow tongue coating, kudzu root can work with bupleurum root, baical skullcap root, and Dahurian angelica root to expel heat pathogens from the muscles and skin. In case if individuals have obvious chills, aversion to wind blowing, no sweating, neck and shoulder stiffness, then kudzu root can work with ephedra, cassia twig, white peony root and liquorice root to expel wind and cold pathogens from the muscles and skin.
Kudzu root promotes eruption to detoxify
Kudzu root is often used in rash problems such as measles, the herb promotes the skin eruption process and facilitate recovery. Kudzu root often works along with bugbane rhizome, red peony root and liquorice root for the conditions. Sometimes, peppermint, great burdock fruit, schizonepeta herb and cicada slough are used to work with kudzu root.
Kudzu root reduces fever and promotes fluid production
Kudzu root is ideal for quenching thirst. It can work alone, but will be better when combining with other herbs. For feverish individuals who accompanied with thirst, kudzu root can work with gypsum and anemarrhena rhizome in the remedy. After recovered from feverish conditions, some individuals may still have persistent thirst, it is proper to use kudzu root along with dwarf lily-turf tuber, dendrobium and reed rhizome to resume a normal fluid metabolism. When internal heat disturbed body fluid metabolism, individuals can have excessive drinking and eating, which similar diabetic conditions, physician may use kudzu root along with herbs like smoked plum, snakegourd root, dwarf lily-turf tuber, pilose asiabell root and astragalus root in the remedies.
Kudzu root promotes the up-flow of pure-qi in spleen and stomach to stop diarrhea
Infection of the intestines may result in severe diarrhea, which is regarded as a damp-heat disharmony in TCM, physicians use kudzu root along with baical skullcap root, golden thread rhizome and liquorice root for the treatment; when the diarrhea is bloody or occurred after drinking, kudzu root can work with rehmannia root, baical skullcap root and bitter orange for the treatment. Chronic diarrhea is usually associated with spleen deficiency, which can be treated by kudzu root in combination with ginseng, poria, and liquorice root.
Modern TCM often uses kudzu root in the treatment of feverish conditions, intestinal flu, enteritis, hypertension accompanied with dizziness, headache or neck stiffness, coronary problems accompanied with pain and stuffiness in the chest, stroke complications, cervical spondylosis, diabetes, retinal disorder and sudden deafness.
Kudzu root is also a common soup ingredient in Southern China.
Pharmacological Actions
Studies showed that kudzu root has effects in reducing fever, anti-inflammation, anti-bacteria, expanding blood vessels in the heart and brain, β-blocking extensively, reducing heart beating, lowering blood pressure, muscle relaxing, anti-coagulation, regulating immune and blood sugar levels, antioxidant, anti-tumor, skin beauty and estrogenic hormonal benefits.3,5,6
Toxicology
Puerarin via intravenous injection to rat, the LD50 was found to be 738.1mg/kg or 1g/kg. The maximal dose of puerarin (172.2 mg/kg) to rat via intraperitoneal injection, and the maximal dose of puerarin (91.3mg/kg) to rabbit via intravenous injection, for 14 consecutive days, nothing abnormal was found in the behavior, blood pictures, biology and organ structures. The results indicate that kudzu root has minimal toxicity.5
Administration and Dosage
Taking orally, the usual dosage for kudzu root is 9〜15g, or can be higher to 15〜30g. It is recommended to use dried herb for the purposes of reducing fever and promoting fluid production, while for the purposes of stop diarrhea, the herb has to be processed.3,5
Adverse Effect, Side Effects and Cautions
Clinical demonstrations show that it is safe to take kudzu root orally within the suggested dosage; there is no adverse response even for a large dose (below 30g) or long-term consumption. However, individuals with stomach problems, hypotension and a slow heart beating should take kudzu root with caution.5
References
- Li Jiashi (editor-in-chief), Chinese Medicine Identification, Shanghai Scientific and Technical Publishers, 2000-2.
- Jiang Su New Chinese Medicine College (edited), Chinese Medicine Encyclopaedia, Shanghai Scientific and Technical Publishers, 2005-5.
- Lui Daiquan (editor-in-chief), Chinese Herbal Medicine, Shanghai Scientific and Technical Publishers, 2000-6.
- Tao Yufeng, Clinical Herbal Medicine, People's Medical Publishing House, 2005-5.
- Chen Pian, Clinical Application of Tonifying Herbs, Second Military Medical University Press, 2008-8.
- http://www.zysj.com.cn/zhongyaocai/yaocai_f/fuling.html
