✵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 Phytolaccae(Pokeberry Root).
Brief Introduction: The herb Radix Phytolaccae is the dried root of Phytolacca acinosa Roxb.or Phytolacca americana L.(family Phytolaccaceae), used as a diuretic and hydragogue for treating edema and ascites, also used externally for treating boils and sores. The herb is commonly known as Radix Phytolaccae, Pokeberry Root, Shānɡ Lù.
✵Official herbal classics and other famous herbal classics defined the herb Radix Phytolaccae(Pokeberry Root) as the dried root of the species (1). Phytolacca acinosa Roxb., or (2). Phytolacca americana L. They are plants of the Phytolacca L. genus, the Phytolaecaceae family of the Centrospermae order. These 2 commonly used species are introduced as:
(1).Phytolacca acinosa Roxb.: It is commonly known as Shānɡ Lù. Perennial herbs, 0.5~1.5 meters tall, glabrous. Root hypertrophy, fleshy, obconical, flaxen or grayish brown, yellowish-white inside. Stem erect, cylindrical, longitudinally furrowed, succulent, green or reddish-purple, much-branched. Leaf-blade thinly papery, elliptic, oblong or lanceolate elliptic, 10~30 cm long, 4.5~15 cm wide, apex acute or acuminate, base cuneate, tapering, fine white spots scattered on both sides (needle crystal), midrib convex on abaxially. Petiole 1.5~3 cm long, stout, grooved above, semicircle below, slightly flattened at base.
Racemes terminal or opposite to leaves, terete, erect, usually shorter than leaves, densely flowery; Peduncle 1~4 cm long; Bracts linear at base of pedicel, ca. 1.5 mm long, upper 2 bracteoles linear-lanceolate, homogeneous; Pedicels slender, 6~10~13 mm long, base thickened; Flowers bisexual, ca. 8 mm in diameter. 5 tepals, white, yellow-green, elliptic, ovate or oblong, apex obtuse, 3~4 mm long, ca. 2 mm wide, equal in size, often reflexed after flower; 8~10 stamens, subequal as tepals, filaments white, subulate, base flaky, persistent, anthers elliptic, pink; Carpels are usually 8, sometimes as little as 5 or as much as 10, detached; Style is short, erect, apex recurved, stigma inconspicuous.
Fruit stock erect; Berry oblate, ca. 7 mm in diam., black when ripe; Seeds reniform, black, ca. 3 mm long, 3-edged.
Ecological environment: The plant grows in a thin forest or garden. It often grows widely at the foot of the mountain, in the forest, along the road, and in front of the house. It prefers a warm and humid climate, resistant to cold and waterlogging, and the temperature suitable for growth is 14~30℃. The above-ground part withers in autumn and winter, while the underground fleshy root can withstand the low temperature of -15℃. Wide adaptability to the soil, whether it is sandy soil or red loam, whether the soil is fertile or barren, can grow luxuriant foliage. The plant mainly distributes in the southwest to the north area of China, it also distributes to other areas of East Asia and South Asia.
Trait identification: Root conical, with many branches. The surface is grayish brown or yellowish, with obvious transverse lenticels and longitudinal furrows. Goods are mostly pieces that are cut horizontally or longitudinally. The transverse section is irregularly round, with wrinkled edges, 2~8 cm in diameter and 2~6 mm in thickness. The section is light yellow or yellow-white, with several uneven concentric rings. The longitudinal section is irregular rectangular, curved or curly, 10~14 cm long and 1~5 cm wide, with an uneven surface and most raised longitudinal stripes on the wood part. Hard and not easily broken. Smells light, sweet light, long chewing benumbing the tongue.
(2).Phytolacca americana L.: It is commonly known as Chuí Xù Shānɡ Lù. Perennial herbs, 1~2 meters tall. Roots stout, hypertrophic, obconical. Stem erect, cylindrical, sometimes purplish red.
Leaf blade elliptic ovate or ovate-lanceolate, 9~18 cm long, 5~10 cm wide, apex acute, base cuneate; Petiole 1~4 cm long.
Racemes terminal or lateral, 5~20 cm long; Pedicels 6~8 mm long; Flowers white, microstrip reddish, ca. 6 mm in diameter; 5 tepals, stamens, carpels and styles usually 10, carpels united.
Fruit stock pendulous; Berries are oblate, purplish-black when ripe; Seed kidney rounded, ca. 3 mm in diameter. Its flowering period is from June to August, fruiting from August to October.
Ecological environment: The plant grows under trees, in the thin forest, on the roadside, wasteland, and damp places near houses. The plant originally distributes in North America, it was introduced cultivation after 1960 and grows throughout China, and it mainly distributes in the middle and lower Yangtze River area, the Zhujiang river area, the middle reaches area of the Yellow River, north area of China.
Trait identification: the herb shape is similar to the root of Phytolacca acinosa Roxb.