✵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:
Flos Genkwa(Lilac Daphne Flower Bud).
Brief Introduction: The herb Flos Genkwa is the dried flower-bud of Daphne genkwa sieb.et Zucc.(family Thymelaeaceae), used as a hydragogue and purgative for treating severe edema, hydrothroax and ascites with oliguria and constipation, and externally for scabies and frostbite. The herb is commonly known as Flos Genkwa, Lilac Daphne Flower Bud, Yuán Huā.
✵Official herbal classics and other famous herbal classics defined the herb Flos Genkwa(Lilac Daphne Flower Bud) as the dried flower-bud of the species (1).Daphne genkwa sieb.et Zucc. It is a plant of the Daphne Linn. Genus, the Thymelaeaceae family of the Myrtales order. This commonly used species is introduced as:
(1).Daphne genkwa sieb.et Zucc.: It is commonly known as Yuán Huā. A deciduous shrubs, 0.3~1 meter tall, much-branched; Bark brown, glabrous; Branchlets cylindrical, thin, wrinkled after drying, young branchlets yellow-green or purplish-brown, densely flaxen filamentous pilose, old branchlets purplish-brown or purplish-red, glabrous.
Leaves opposite, thin alternate, papery, ovate or lanceolate to oval elliptical oblong, 3~4 cm long, 1~2 cm wide, apex acute or acuminate, base broadly cuneate or obtuse rounded, margin entire, the green, dark brown after drying, the pale green, after drying yellow-brown, densely covered with silk was yellow villous, only when they had been old leaf base bulk raw silk yellow villous, lateral veins 5-7 pairs, it is significantly below; Petiole short or nearly absent, ca. 2 mm long, gray pilose.
Flowers open earlier than leaves, purple or bluish-purple flowers, often 3~6 flowers clustered in leaf axils or lateral, open earlier than leaves, easy to distinguish from other species. Pedicels short, glaucous pilose; Calyx tube slender, tubular, 6~10 mm long, outside with filiform pilose, 4 lobes, ovate or oblong, 5~6 mm long, 4 mm wide, apex rounded, outside sparsely pubescent; 8 stamens, 2 inserted in the upper and middle of the calyx tube, filaments short, ca. 0.5 mm long, anthers yellow, ovoid elliptic, ca. 1 mm long, extending larynx, apex obtuse; Disk annular, undeveloped; Ovary long obovate, 2 mm long, densely yellowish pilose, style short or absent, stigma capitate, orange-red.
Fruit fleshy, white, elliptic, ca. 4 mm long, enveloped in the lower part of persistent calyx tube, with 1 seed. Its flowering period is from March to May, fruiting from June to July.
Ecological environment: The plant grows on roadsides, hillsides, or gardens, at an altitude of 300~1,000 meters above sea level. The plant is suitable for a warm climate, drought tolerance, and fear of waterlogging, suitable for cultivation in fertile and loose sandy soil. The plant distributes in the middle and lower reaches areas of the Yangtze River, the Hanjiang river area, and other areas of China.
Trait identification:Dried flower buds curved or slightly flattened club-shaped, ca. 1 cm long, ca. 0.3 cm in diameter, usually single or 3~7 in clusters. The upper end is slightly enlarged, split into 4 pieces, yellowish-brown, lower-end finer, grayish brown, dense white nap. The flower heart is harder, show burgundy. The whole flower is soft. The smell is sweet, the long smell can cause a headache, the taste is sweet. It has a spicy taste. The herb with many flower buds and tidy, color lavender is better.