Calamus. - Synonym. - Sweet Flag. The rhizome of Acorus Calamus Linne (nat. ord. Aroideae).

Habitat

Europe and North America, on the banks of streams and ponds.

Characters

In sections of various lengths, unpeeled, about 2 cm. broad, subcylindrical, longitudinally wrinkled; on the upper surface marked with leaf-scars forming triangles, and on the lower surface with the circular scars of the rootlets in wavy lines; externally reddish-brown, somewhat annulate from remnants of leaf-sheaths; internally whitish, of a spongy texture, breaking with a short, corky fracture, showing numerous oil-cells and scattered wood-bundles, the latter crowded within the subcircular endoderm. It has an aromatic odor, and a strongly bitter taste. As found in the shops it is generally peeled.

Composition

The chief constituents are - (1) Acorin C36H60O6, a bitter glucoside, as a syrupy, yellow liquid. (2) Volatile oil, I to 2 per cent. (3) Calamine, an alkaloid. (4) Choline.

Preparation

Extractum Calami Fluidum. Fluid Extract Of Calamus

By maceration and percolation with Alcohol, and evaporation. Dose, 15 to 60 m.; 1. to 4. c.c.

Action And Uses Of Calamus

Sweet flag is a simple bitter and feeble aromatic, and is used with advantage in pain or uneasiness in the stomach or bowels arising from flatulence, or as an adjuvant to purgative medicines.