540. Viburnum Opulus, N.F.—Cramp Bark. High Bush Cranberry.
DESCRIPTION OF DRUG.—Very thin pieces or occasionally quills, outer surface, light gray, with purplish-brown stripes and very small brown lenticels; thicker pieces purplish-red, or occasionally blackish; odor strong and characteristic; taste bitter; the inner surface is yellowish or brownish; fracture short. The bark of the mountain maple (Acer Spicatum) was an adulterant formerly described by misled authorities, as Viburnum opulus.
Powder.—Light brown. Characteristic elements: Parenchyma of inner cortex, with rosettes of calcium oxalate; middle bark bearing reddish-brown coloring matter, starch (5 to 12 µ in diam.); tracheal fragments with lignified wood fibers; few stone cells; crystals of calcium oxalate, few aggregate (15 to 30 µ in diam.); polygonal cork cells, thin-walled.
ACTION AND USES.—Claimed to be antispasmodic, hence the name cramp bark. Dose: 30 gr. to 2 dr. (2 to 8 Gm.).