The Greek physician and botanist of the first century, Dioscorides, highlighted the knotweed benefits for people who coughed up blood and women suffering from excessive menstruation. Due to its hemostatic effect (capable of stopping hemorrhages), the Romans called the plant sanguinaria (bloody), which lives on in many places.
In the 19th century, when tuberculosis decimated the population of the unhealthy towns, knotweed was the object of a profitable business. It was recommended and sold to fight tuberculosis; its hemostatic effect stopped the bronchial and lung hemorrhage of people suffering from tuberculosis. This is a sad example of the mistakes that a badly employed phytotherapy may lead to. Fighting the symptoms (bronchial bleeding) was intended to heal the disease (tuberculosis).
We now know the chemical composition and the properties that make up knotweed benefits and many other plants. But if treatments, whether with medicinal herbs or with pharmaceutical medicines, are not correctly applied, there exists the risk of mistaking the symptoms for the disease.
Knotweed Scientific Facts
- Scientific Name – Polygonum aviculare L.
- Other Names – Knotgrass, beggarweed, bind knotgrass, birdweed, cow grass, common knotweed, crawlgrass, doorweed, ninety-knot, pigweed.
- French – Renouée des oiseaux
- Spanish – Centinodia, hierba nudosa.
- Environment – Common on roadsides and dry soils worldwide.
- Description – Creeping plant of the Polygonaceae family, growing on roadsides and crossing roads, with knotted, thin stem, elongated leaves growing from the knots, and small, white, purple, or pink flowers.
- Parts of the plant used medicinally – The entire plant.
Knotweed contains tannins, flavonoids, silicon, mucilage, and essential oil. Its hemostatic action, which promotes blood coagulation, is mainly due to its high tannins content, which has the property of coagulating proteins. Besides, flavonoids increase the resistance of the cells that form the walls of the blood vessels (especially of the capillaries), thus stopping internal bleeding.
The maximum combined effect of both substances is mainly achieved in the digestive system. Thus, knotweed benefits especially suit any inflammation with bleeding that is produced in the intestine and the stomach:
- Gastroenteritis and dysentery (diarrhea accompanied by bleeding): Its effect in these cases is notable since, besides healing diarrhea, it stops the bleeding.
- Hemorrhagic gastritis and bleeding gastroduodenal ulcers: Due to the level of severity that hemorrhage can reach, only a physician can prescribe the use of this plant. Knotweed is also helpful in other types of bleeding.
- Mild hemoptysis (bronchial-lung hemorrhage that manifests with blood appearing together with sputum): Bear in mind that the knotweed, though it helps stop the bleeding, does not heal the causative disease (tuberculosis, cancer, etc.).
- Excessive menstruation: Before taking a decoction of knotweed, women have to undergo a gynecological examination.
Due to its content in essential oil, along with other active components, knotweed also has a mild diuretic effect (increases urine production).
How to use Knotweed
- Decoction with 30 to 50 grams of flowering plant (when it is more effective) per liter of water. Boil for ten minutes and strain; sweeten as you like. Drink four or five cups daily, though this dosage can be exceeded without any risk since this plant lacks any toxic effects.
- Powder. Take from two to five grams three times a day.
George D. Pamplona-Roger, M.D. “Encyclopedia of Medicinal Plants.” George D. Pamplona-Roger, M.D. Encyclopedia of Medicinal Plants. Ed. Francesc X. Gelabert. Vols. 1 San Fernando de Henares: Editorial Safeliz, 2000. 272, 273. Print. [knotweed benefits]