Knotweed

Last Editorial Review: 6/11/2021
Other Name(s):

Allseed Nine-Joints, Anjubar, Armstrong, Aviculaire, Beggarweed, Bian Xu, Bird's Tongue, Birdweed, Centinode, Centinodia, Cow Grass, Crawlgrass, Doorweed, Herbe aux Cent Nœuds, Herbe à Cochon, Herbe aux Panaris, Herbe des Saints-Innocents, Hogweed, Knot Grass, Knotweed Herb, Lengua de Pajaro, Lis Glané, Mexican Sanguinaria, Ninety-Knot, Pigrush, Pigweed, Polygoni Avicularis Herba, Polygonum aviculare, Red Robin, Renouée des Oiseaux, Sanguinaria, Sparrow Tongue, Swine Grass, Swynel Grass, Tire-Goret, Trainasse, Vogelknoeterichkraut, Yerba Nudosa.

Overview

Knotweed is an herb. The whole flowering plant is used to make medicine.

Knotweed is used for bronchitis, cough, gum disease (gingivitis), and sore mouth and throat. It is also used for lung diseases, skin disorders, and fluid retention. Some people use it to reduce sweating associated with tuberculosis and to stop bleeding.

How does work?

Knotweed might be able to reduce swelling. It might also prevent plaque from building up on teeth.

QUESTION

Next to red peppers, you can get the most vitamin C from ________________. See Answer

Uses

Insufficient Evidence to Rate Effectiveness for...

  • Gum disease (gingivitis). Developing research suggests that a root extract of knotweed might be useful as a mouth rinse to treat gingivitis. Gingivitis is caused by plaque, a film of saliva and bacteria that builds up on teeth at the gum line. The knotweed extract seems to decrease bleeding and swelling of the gums, possibly because it might interfere with the formation of plaque.
  • Bronchitis.
  • Cough.
  • Lung diseases.
  • Skin diseases.
  • Fluid retention.
  • Decreasing sweating associated with tuberculosis.
  • Stopping bleeding.
  • Other conditions.
More evidence is needed to rate the effectiveness of knotweed for these uses.

Side Effects

Knotweed may be safe for most people, but the possible side effects of knotweed are not known.

Precautions

Pregnancy and breast-feeding: Not enough is known about the use of knotweed during pregnancy and breast-feeding. Stay on the safe side and avoid use.

Dosing

The appropriate dose of knotweed depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for knotweed. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

SLIDESHOW

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Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

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References

Gonzalez Begne M, Yslas N, Reyes E, et al. Clinical effect of a Mexican sanguinaria (Polygonum aviculare L.) on gingivitis. J Ethnopharmacol 2001;74:45-51.. View abstract.