Acorus calamus.  水 菖 蒲  Shuǐ chāng pú   Sweet flag, Calamus  Family: Araceae   
Nature- warm- neutral     FLAVOR: Biting, pungent
FUNCTIONS
GROUP: Aromatic Stimulants
1. Expels gas, alleviates constipation.[1]
2. Resolves phlegm.[1] Expel sputum transform Dampness. Harmonize the Stomach.[2]
3. Kills worms, detoxifies.[1]
4. Open up cavities.[2]
INDICATIONS
1. Epilepsy and strokes.[1]
2. Rheumatoid arthritis.[1]
3. Stomach ache, edema, toxic dysentery.[1]
PREPARATIONS: Decoction 3-6 g. For  external use, fresh roots and stems are crushed for application.[1] Dried rhizome.[2]
HABITAT: Usually found growing in paddy field and other damp areas along stream banks.
DESCRIPTION: Perennial aquatic herb. Whole plant emitting characteristic fragrance. Rhizome; thick and fleshy, subterranean stolon with numerous nodes, light red. Leaves; clustered from rhizome, in parallel arrangement, lanceolate, midrib obvious, apexes acute, bases enclosing stem. Flowers; in summer, yellowish-green, appearing from apex, forming a fleshy spadix inflorescence. Fruit; an ovoid-round berry, red when ripe.
References
Inner Path can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.
Constituents.
Bitter volatile oil 1.5-3.5% containing b-[3]asarone to 80%,[1,2] up to 96% in the varieties- vulgaris, angustatus and versus.[3] In Acorus calamus var americanus, b-aserone and other phenylpropanoids are absent, and the main constituents are the sesquiterpenes shyobunone, 6-epishyobunone, 2,6-diephishyobunone; together with up to 35% isacorone, 25% acorone and acorenone and small amounts of calamendiols.[3] Other constituents of the oil are sesquiterpene hydrocarbons such as l-cacala-1,4,9-triene, guaiane sesquiterpene ketones,[4] acoragermacrone,[5] acolamone, isacolamone, pinene, aculene, methyleugenol, methylisoeugenol, camphor, asoraldehyde and acoric acid.[6]
Eugenol and asamyl alcohol.[1]
Bitter principle Acorin.[1,2]  Tannin.[1]  Starch.[1]
References
[1] British Herbal Pharmacopoeia 1983 Published by the British Herbal Medicine Association ISBN 0 903032 07 4.
[2] Herbal Materia Medica Course Notes For Diploma of Naturopathy and Diploma of Herbalism Students by Lydia Mottram.
[3] Keller, K. et al. (1985) Planta Med. 51 (1), 6
[4] Rohr, M, and Naegeli, P. (1979) Phytochem. 18 (2), 279
[5] Iguchi, M. et al. (1973) Tet. Lett. 29, 2759
[6] Encyclopedia of common Natural Ingredients used in Food Drugs and Cosmetics, Albert Y. Leung. Pub. John Wiley & Sons Inc. (1980) NY
Images
1. en.wikipedia.org by J.F. Gaffard, Autoreille, France CC BY-SA 3.0
2. jadibutinepal.com
3. godasagardener.com
Research.

Pharmacological studies in China have shown that extracts of Calamus have anti-arrhythmic, hypotensive, vasodilatory, antitussive, antibacterial and expectorant activity.[1]
Toxicity studies there showed that the oil was of low toxicity in animals and adverse reactions in patients rare.[1]
It has been shown that b-asarone is carinogenic in animals; however recent studes have demonstrated that Acorus calamus var americanus, which does not contain b-asarone, is in fact superior in spasmolytic activity to the other types.[2] Therefore, although abolute safety has not been proven yet, it would be preferable to use this variety for internal use.[3]
Preparations containing b-asarone are banned from sale in the USA.[3]
References
[1] Pharmacology and Aplications of Chinese Materia Medica Vol 1, Ed. H. chan and P. But, Pub. World Scientific (1986) Singapore
[2] Keller, K. et al. (1985) Planta Med. 51 (1), 6
[3] Potter's New Cyclopaedia of Botanical Drugs and Preparations  R.C. Wren Revised by Elizabeth M. Williamson and Fred J Evans. First published in Great Britain in 1988 and reprinted in 1989 and 1994 by the C. W. Daniel Company Limited. 1 Church Path, Saffron Walden Essex. Published 1988 Printed and bound by Biddles, Guildford ISBN 085207 1973.