The Chinese herbal medicine Da Wei Yao is the whole plant or root of the plant Da Wei Yao, which belongs to the family Rubiaceae. It is mainly distributed in Fujian, Taiwan, Guangdong, Hainan, Guangxi, Yunnan, and other regions in China. Da Wei Yao has the effects of clearing heat, detoxification, and diuresis. In traditional Chinese medicine, it is used to treat infantile convulsions. Let's take a closer look at Da Wei Yao!
【Morphological Characteristics of Da Wei Yao】
Da Wei Yao, also known as Gou Wei Cao or Quan Chong Cao, is an annual herbaceous plant that grows to a height of 15-60cm. The root is cylindrical and turns yellow-brown when dry. The stem is erect, stout, and branches frequently, covered with rough hairs.
The leaves are opposite or nearly opposite; the petiole is 2-5cm long. The leaf blade is ovate or elliptic, 4-10cm long, 2-4cm wide, with a short or gradually pointed apex, and a rounded or truncate base that extends down to the petiole. The margin is slightly serrated or wavy, and both sides are sparsely covered with short rough hairs. The inflorescence is scorpion-like umbel, 5-20cm long, slender and curved, solitary, unbranched, terminal or opposite to the leaf, without bracts. The flowers are small and densely arranged in two rows on one side of the inflorescence axis. The calyx is deeply divided into 5 lanceolate lobes, covered with rough hairs. The corolla is light blue or blue-purple, rarely white, tubular with a high foot, 3-5mm long, and shallowly divided into 5 lobes at the apex. The lobes are nearly circular, expanded, the throat is smooth without appendages. There are 5 stamens hidden inside the corolla tube. The ovary is small, and the stigma and style are very short. The style forms a broad conical shape with a flat tip. The fruit is ovoid, 4-5mm long, with longitudinal ribs and 2 deep lobes. Each lobe is divided into 2 sublocules, each containing a single seed. The flowering period is from April to July, and the fruiting period is from August to October.
【Treatment of Infantile Convulsions with Da Wei Yao】
12g of dried Da Wei Yao root and 9g of dried Huang Dan Cao are stewed with a little salt in water and taken orally.
In traditional Chinese medicine, Da Wei Yao is believed to have the effects of clearing heat, detoxification, and diuresis. It is used for the treatment of pneumonia, empyema, sore throat, oral ulcers, bladder stones, and abscesses.
1. "Guangxi Materia Medica Compilation": "Clears heat, detoxifies, drains pus, and reduces swelling."
2. "National Compilation of Chinese Herbal Medicines": "Clears heat, detoxifies. Mainly used for the treatment of pneumonia, lung abscess, empyema, diarrhea, dysentery, orchitis, diphtheria, oral ulcers, and abscesses."
【Pharmacological Effects of Da Wei Yao】
The aqueous extract of Da Wei Yao root can lower blood pressure and stimulate respiration when injected intravenously into anesthetized cats. It has an inhibitory effect on the isolated frog heart. However, the alcoholic extract has no effect.
The aqueous extract has no significant effect on the isolated guinea pig ileum but can increase the tension of the isolated rabbit duodenum. In contrast, the alcoholic extract has an inhibitory effect on both tissues.
It has no effect on the abdominal muscle of frogs but significantly stimulates the uterus of isolated rats. Both the aqueous and alcoholic extracts have oxytocin-like effects.
The leaf extract of Da Wei Yao has an anti-tumor effect (prolonging lifespan) on Schwartz leukemia (ascitic type) in mice.
