Local names: Xuong bo, Thach xuong bo, Thuy xuong bo
English name: Dwarf sedge, Japanese rush, Japanese sweet flag, Grass-leaved sweet rush.
Pharmaceutical Name: Rhizome Acori graminei
Description:
Perennial semi-aquatic herb. Rhizome aromatic, creeping and much-branched. Leaves long and amplexicaul, in fascicles; principal nerves parallel. Inflorescence in spike on a compressed scape, surrounded by a long bract; flowers small, bisexual. Berry bright-red when ripe.
Other species, such as Acorus calamus L. and A. gramineus Soland. var. pusillus Engl. are also used medicinally.
Part Used & Method for Pharmaceutical Preparations:The rhizomes are dug in early spring and cleaned and dried in the sun. When the fresh rhizome is used for medical purposes, it should be dug in late summer.
Distribution: Grows wild on the banks of mountain streams.
Chemical composition:
The rhizome contains an essential oil consisting of asaron and asaryl aldehyde; and a bitter glucoside, acorin.
Therapeutic uses:
The rhizome possesses pectoral, stomachic and sedative properties. It is utilized in the therapy of diarrhoea, gastralgia, cough, bronchial asthma, neurasthenia, fever, convulsions, rheumatism, osteodynia and arrhythmia.
Indications & Combinations:
Indications & Combinations:
1. Unconsciousness due to blockage of the pericardium by turbid phlegm or accumulation of dampness and heat. Grass-leaved sweetflag (Thach xuong bo) is used with fresh Bamboo juice (Truc nhu) and Curcuma root (Uat kim) in the formula Xuong bo Uat kim Thang.
2. Dampness blocking the middle jiao (spleen and stomach) manifested as stifling sensation, distension and pain in the chest and abdominal region. Grass-leaved sweetflag (Thach xuong bo) is used with Tangerine peel (Tran bi) and Magnolia bark (Hau Phac).
3. Damp-heat blocking the middle jiao manifested as dysentery and vomiting after meals. Grass-leaved sweetflag (Thach xuong bo) is used with Coptis root (Hoang lien).
4. Insomnia, forgetfulness, tinnitus and deafness. Grass-leaved sweetflag (Thach xuong bo) is used with Polygala root (Vien chi) and Poria (Phuc linh) in the formula Anshen Dingzhi Wan.
Dosage: The daily dose is 3 to 8g in the form of a decoction, powder and pills, for a period of 1 to 2 months. External application is effective for dermatosis and haemorrhoids. It is also used as an insecticide for killing lice, bugs and fleas (double dosage for the fresh herb).