Nettles in Chinese Medicine?
Nettles in Chinese Medicine?
By Eric Brand
The other day I received a very interesting inquiry from one of our local experts in Chinese medical gynecology. Apparently there is some fascinating research coming from Western herbal medicine on the use of nettle root for the treatment of PCOS, and the practitioner asked me about the TCM actions for nettles. Nettles are found in the Zhong Yao Da Ci Dian (Great Encyclopedia of Chinese Medicinals), and both the whole herb and the root are described. We were interested to see if there was any traditional use of nettles in the context of gynecology, so I am posting a translation of the TCM properties of nettles below:
The precise species of nettles used in Chinese medicine is slightly different from the species most commonly found in Western herbal medicine. In China, the plants Urtica cannabina L. and U. angustifolia Fisch. ex Hornem are used, and they are known in Chinese as qian ma (whole herb) and qian ma gen (root). In the West, nettle is derived from Urtica dioica L. and U. urens L. The clinical significance of this botanical difference is unclear to me, and the two items show notable differences in use between the Chinese and Western literature. In Western literature (such as the ESCOP Monographs from Europe), we find that much of the clinical use of nettle root focuses on urination problems, whereas much of the Chinese literature emphasizes the treatment of wind-damp disease and blood stasis.
According to the Zhong Yao Da Ci Dian, the root of nettle is bitter, acrid, and warm, and it is said to be toxic. It dispels wind, quickens the blood, and relieves pain. It is indicated for wind-damp pain, eczema, and “numbing wind” (leprosy). Another text from the local medicine traditions of Guizhou province says that nettle root treats vacuity taxation damage, soothes the sinews and quickens the blood, and expels wind. A handbook on medicinals from Xinjiang province says that it can treat high blood pressure and numbness of the extremities. Internally, it is used at a dose of 0.5-1 liang (about 15-30 g in the PRC), and can also be soaked in alcohol. Overdosage is associated with vomiting, abdominal pain, dizziness, and palpitations; in severe cases vacuity desertion may occur. In addition to treating these symptoms of overdose, a drink made from fresh ginger and red sugar can be given in the case of overdose.
The nettle herb (aerial portion) is used in a similar fashion, but it is said to be cold, not warm. Nettle herb is acrid, bitter, cold, and toxic. It treats wind-damp pain, postpartum “tugging wind” (biomedical correspondence: clonic spasms), childhood fright wind (convulsions in children), and urticaria. Interestingly, the biomedical term “urticaria” is related to the name of this plant in both Latin and Chinese. By decoction, a dose of 1-3 qian is used (3-9 g in PRC or about 4-11 g everywhere else), and it can also be double-boiled with meat. Externally it can be used by crushing it to extract its juice or by decocting it for use as a wash.