✵The TCM herbalism is also known as pharmaceutics of Traditional Chinese Medicine, or Chinese pharmaceutics, is the branch of health science dealing with the preparation, dispensing, and proper utilization of Chinese herbs. It is majorly composed of Introduction of Chinese Medicinals, Classification of Chinese Herbs, Formulas, and Patent medicines.
Classifications of Herbs:Diuretics and Hydragogues Herbs:Herbs Hydragogues or Drastic Purgatives.
Introduction: Herbs Hydragogues or Drastic Purgatives: also known as diuretic hydragogue herbs, an agent or substance herbs that causes copious discharge of water through catharsis and at the same time increases urine excretion.
✵Till the date Oct 10th,2019, there are totally  kinds of common TCM herbs,  kinds of related plant species, are recorded in this category. These diuretics and hydragogues herbs: hydragogues or drastic purgatives herbs are briefly introduced separately:
Radix Euphorbiae Kansui(Kansui Root).
Brief Introduction: The herb Radix Euphorbiae Kansui is the dried tuberous root of Euphorbia kansui T.N.Liou ex T.P.Wang(family Euphorbiaceae), used as a hydragogue and purgative for hydrothorax and ascites with oliguria and constipation. The herb is commonly known as Gansui Root, Root of Gansui, Root of Kansui, Radix Euphorbiae Kansui, Gān Suí.
✵Official herbal classics and other famous herbal classics defined the herb Radix Euphorbiae Kansui(Kansui Root) as the dried tuberous root of the species (1).Euphorbia kansui T.N.Liou ex T.P.Wang. It is a plant of the Euphorbia L. genus, the Euphorbiaceae family of the Malpighiales order. This commonly used species is introduced as:
(1).Euphorbia kansui T.N.Liou ex T.P.Wang.: It is commonly known as Gān Suí. Perennial herbs, 25~40 cm tall. The whole plant contains white milk. Root slender, curved, middle and end often beaded, finger-shaped or long oval root, brown appearance. Stem often branched from base, purplish-red below, pale green above. Leaves alternate; Sessile; Leaf blade linear-lanceolate and narrowly lanceolate, 2~9 cm long, 4~10 mm wide, apex obtuse, base cuneate, entire. Cup cymes terminal, 5~9 pedicels, basal whorls oblong or narrowly ovate, 1.5~2 cm long, 8~9 mm wide; Each stalk often bifurcated again, slender, 2~4 cm long; Bracts 1 pair, triangular-ovate, 5~9 mm long, entire. Involucre gyrally shaped, ca. 2 mm long, apex 4-lobed, lobes ovate-triangular, margin with white hairs, 4 glands, crescent, yellow, angular at both ends, grow at outer margin between lobes; 8~13 male flowers, 1 stamen per flower; 1 female flowers, central one is male, 3 styles, detached, stigma 2-lobed. Capsule subglobose, glabrous, grayish brown, ca. 2 mm. Its flowering period is from April to June, fruiting from June to August.
Ecological environment: The plant grows mostly in grassy slope, farmland ridge, barren slope, sandy land, low slope, grassy slope, farmland ridge, roadside, etc. The plant mainly distributes in the north, the middle reaches area of the Yellow River, northwest, southwest area, and other areas of China.
Cultivation biological characteristics: The plant prefers cool climate, cold tolerance. Its growth requirements on the soil are not strict, the above layer deep, loose and fertile. It is advisable to cultivate on sandy or clay soil with good drainage and rich humus.
Trait identification: the root is elliptic, long cylindrical or beaded, 1~5 cm long, 0.5~2.5 cm in diameter. The surface of the embolus is white or yellow-white, and brown embolus remains in the depression. Not to the brown-red emboli, there are obvious longitudinal grooves and a few transverse lenticels. Crisp, easy to break, broken flour, white skin, wood, light yellow, radial texture; Long terete is more fibrous. Light smell, taste slightly sweet, spicy, stimulating. To hypertrophy. The herb which color is white, with sufficient powder content is better.