Calamus combines demulcent effects of the mucilage with the carminative effect of the volatile oil and the stimulating effect of the bitters. It is thus an excellent tonic for the whole gastro-intestinal tract. It may be used in dyspepsia of all kinds, in gastritis and gastric ulcers. It will stimulate a flagging appetite and help to ease exhaustion and weakness when there is a digestive involvement. It may be considered a specific in colic due to flatulence. The New Holistic Herbal by David Hoffmann Pg. 187