The rhizome and rootlets of the Asarum canadense, Linné.
COMMON NAMES: Wild ginger, Indian ginger, Canada snakeroot, and (improperly) Coltsfoot.
Botanical Source.—This American plant closely resembles the asarabacca of Europe (A. Europaeum). It has a creeping, fleshy, somewhat jointed, yellowish rhizome, with rootlets. From it ascends a quite short stem, which is forked near the surface of the soil, and each branch bears a reniform leaf, downy on both sides, 3 or 4 inches by 3 or 5, the petiole of which is long, round, and hairy. Upon a pendulous, hairy peduncle, growing from the fork of the stem, is a solitary flower, having a very wooly calyx, consisting of 3 broad, concave, pointed leaflets, of a brownish, dull-purple or greenish color on the inside, at top and bottom, depending on the amount of light which the plant enjoys, terminated by a long, spreading, inflected point, with reflect sides. The corolla is wanting. The fruit is a coriaceous, 6-celled capsule.
Description.—Wild ginger occurs in commerce in irregularly 4-angled pieces, about 9 to 5 inches in length, and about ⅛ inch in diameter. They are crooked, ash-brown, or purple-brown in color, break with a short fracture, are pulverable, and whitish internally. About every half inch exhibits nodes, to which thin rootlets are attached. The inner structure is pithy, surrounded by a broken zone of woody fibers, all enclosed in thick bark, which contains oil cells. The rootlets are traversed by a ligneous, central portion, covered with thick bark. It is fragrant, spicy, and slightly bitter.
History.—Wild ginger is a native of the United States, growing in woods and mountains, and in rich soil along roadsides, flowering in May and June. The whole herb has a fragrant odor, and a spicy, amarous taste. The root is the part used, and yields its active principles to alcohol, and partially to water by infusion. The oil is now used in the making of perfumes, and in various toilet waters.
Chemical Composition.—Asarum contains an acrid, bitter, reddish resin, a pale, spicy, aromatic, volatile oil, gum, chlorophyll, fat, starch, and various salts. It probably, also, contains an alkaloid, as Power obtained a body in very small quantities, which reacted with alkaloid-group reagents. The coloring matter (yellow), as Prof. Power has shown, appears to be the same as the asarin found by Graeger in asarabacca. The oil consists of asarene (C10H16), a neutral principle, asarin (C12H16O2), asarol (C10H18O), and ethers of asarol-probably the acetic and valerianic-and is thought also to contain methyl-eugenol, a substance hitherto not observed in nature.
Action, Medical Uses, and Dosage.—Asarum canadense is a spicy, stimulating agent, causing perspiration, promoting expectoration, and possessing carminative properties. It may be advantageously added to tinctures and compounds to improve their flavor, and render them more stimulating. It is used in colic and other painful affections of the stomach and bowels where no inflammation exists, and in chronic pulmonary affections. It has been successfully used by Dr. J. R. Black in dropsy, with albumen in the urine. The warm infusion is an excellent agent to promote copious sweating, and may be substituted for Virginia snakeroot as a diaphoretic and in debility. Harsh, dry skin, with checked perspiration, in low febrile and inflammatory affections, not of the gastro-intestinal tract, and sudden colds, have been successfully treated with the warm infusion, which is also a prompt emmenagogue when amenorrhoea is due to recent colds. Dose of the powder, ½ drachm; of the tincture, ½ fluid drachm to 2 fluid drachms. Of the infusion (℥ss to aqua Oj), freely; used also as an errhine.