Polygonum cuspidatum, Hu Zhang 虎杖

Bushy Knotweed, Giant Knotweed
Hu Zhang (TCM)
 Picture
Picture Polygonum cuspidatum (as Fallopia japonica)
Curtis, W., Curtis’s botanical magazine (1800-1948)

Picture Polygonum cuspidatum
(Photo  by Superior National Forest) (Wikimedia)

Picture Polygonum Hu Zhang root slice
(Adam, 2024)

Botanical name:


Polygonum cuspidatum (syn. Reynoutria japonica, Fallopia japonica)

Parts used:


Rhizome

Temperature & Taste:


Cold, dry. Bitter

Classification:


K. Move the Blood

Uses:


1. Moves the Blood, Clears the Channels, Eases Pain:
-Amenorrhea, Dysmenorrhea (TCM, West)
-Wind-Damp painful obstructions of the muscles and joints
-Trauma, Bruising

2. Clears Heat and Damp:
-Jaundice, Cholecysitis, Acute Hepatitis
-Turbid, painful and dribbling Urine
-Gravel and Stones of the Bladder and Gall Bladder
-Turbid and foul smelling Leukorrhea

3. Clears Heat and Toxin:
-Boils, Abscesses, Toxic Swellings (TCM, West)
-acute Appendicitis
-Burns, Scalds
-Snakebite, Venomous Insects Bites

4. Clears Phlegm-Heat, Stops Cough:
-Phlegm-Heat Cough, Bronchitis

5. Guides Down, Purges Heat and Bile:
-Constipation from excess Heat
-Hypertension


Dose:


Decoction: 9–15 grams
The fresh leaf may be crushed for external application, or the dried root can be powdered and applied topically.

Comment:


1. Bushy Knotweed (here) is similar in effect to Knotweed (P. aviculare). However, Bushy Knotweed is stronger to move Blood.
2. It is a rich source of resveratrol.

Preparation:


1. Wine Prepared Polygonum Hu Zhang:
  The herb is covered with yellow rice wine, allowed to soak a little, then stir-fried until yellowed and slightly scorched. This makes it more warm, less irritating to the stomach, and better to move the Blood.

Correctives:


Licorice

Substitutes:


1. Knotweed (but not to move Blood)
2. To clear Heat and Damp: Barberry bark or Scutellaria Huang Qin

Main Combinations:


1. Amenorrhea:
i. Polygonurn Hu Zhang with Motherwort (Yi Mu Cao)
ii. Polygonurn Hu Zhang with Dang Gui, Ligusticum Chuan Xiong
2. Dysmenorrhea, Polygonurn Hu Zhang with Ligusticum Chuan Xiong, Corydalis Yan Hu Suo 
3. Painful obstruction of the muscles and joints, Polygonurn Hu Zhang with Spatholobus Ji Xue Teng
4. Pain from Trauma, Polygonurn Hu Zhang with Dang Gui, Myrrh, Safflower
5. Abdominal Masses, Polygonurn Hu Zhang with Rhubarb (Da Huang), Costus (Mu Xiang), Zedoary (E Zhu), Peach kernel (Tao Ren)
6. Jaundice：
i. Polygonurn Hu Zhang with Artemesia Yin Chen Hao
ii. Polygonurn Hu Zhang with Artemesia Yin Chen Hao, Lysmachia Jin Qian Cao, Citrus Qing Pi
7. Turbid Urine, Polygonurn Hu Zhang with Plantain seed (Che Qian Zi), Coix Yi Yi Ren
8. Bladder stones, Polygonurn Hu Zhang with Plantain seed (Che Qian Zi), Lysmachia Jin Qian Cao
9. Stones of the Gall Bladder, Polygonurn Hu Zhang with Costus (Mu Xiang), Bitter Orange (Zhi Ke)
10. Lung Heat Cough, Bronchitis, Polygonurn Hu Zhang with Scutellaria Huang Qin, Loquat leaf (Pi Pa Ye)
11. Toxic Sores, Swellings, Abscesses:
i. Polygonurn Hu Zhang with Lonicera Jin Yin Hua, Forsythia Lian Qiao
ii. Polygonurn Hu Zhang with Dandelion (Pu Gong Ying), Coptis Huang Lian
12. Burns, Gently heat the herb in sesame oil, strain and use when cool.

Major Formulas:


Zheng Gui Shui

Cautions:


1. Not used during Pregnancy.

Toxicity:


Side effects may include dry mouth, nausea, vomiting, abdominal pain, diarrhea.

Main Preparations used: