Black Root

Medical Herbs Catalogue


Black Root

Botanical Name: Leptandra Virginica (NUTT.)
Family: N.O. Scrophulariaceae

Synonyms: Veronica Virginica. Veronica purpurea. Paederota Virginica. Eustachya purpurea and Eustachya alba. Culveris Root. Culver's Physic. Physic Root. Leptandra-Wurzel.
Parts Used: The dried rhizome, roots.
Habitat: Eastern United States.

Description: This tall, herbaceous perennial was included by Linnaeus in the genus Veronica, but was later assigned by Nuttall to the genus Leptandra, a nomenclature followed by present-day botanists. It has a simple, erect stem, 3 or 4 feet high or more, smooth and downy, furnished with leaves in whorls and terminating in a long spike of white flowers, 6 to 10 inches long. The leaves, of which there are from four to seven in each whorl, are lanceolate, pointed and minutely serrate, and stand on short footstalks. A variety with purple flowers has been described as a distinct species under the name of Leptandra purpurea. The plant flowers in July and August. It grows throughout the United States, in the south mostly in mountain meadows - in the north in rich woods, and is not unfrequently cultivated. It will grow readily in Britain. The rhizome and roots are nearly odourless, the taste bitter and rather acrid, and are generally used dried. The rhizome is of horizontal growth, nearly cylindrical, somewhat branched, externally dark brown to purplish brown, smooth and faintly longitudinally wrinkled, and showing stem bases at intervals of 1/2 to 1 1/2 inch. The rootlets, rising from the under portion, are wiry and brittle when dry.

Constituents: The roots contain volatile oil, extractive, tannic acid, gum, resin, a crystalline principle, a saccharine principle resembling mannite, and a glucoside resembling senegin. Both the crystalline principle and the impure resin obtained by precipitating with water a tincture of the root have been called Leptandrin and is said to be the active principle. The properties are extracted by both water and alcohol.

An ester of p-methoxycinnamic acid, a phytosterol verosterol, and some dimethoxycinnamic acid are also obtained.

Medicinal Action and Uses: The fresh root is a violent cathartic and may also be emetic. The dried root is milder and less certain. Leptandrin excites the liver gently and promotes the secretion of bile without irritating the bowels or purging. As it is also a tonic for the stomach, it is very useful in diarrhoea, chronic dysentery, cholera infantum, and torpidity of the liver.

The accounts of its use are conflicting, perhaps owing to the difference in the action of the root in its dry and fresh states. There appears to be a risk of the fresh root producing bloody stools and possibly abortion, though a decoction may be useful in intermittent fever. It has been stated that the dried root has been employed with success in leprosy and cachetic diseases, and in combination with cream of tartar, in dropsy.

Dosages: 15 to 60 grains. Of the impure resin, 2 to 4 grains. Of the powdered extract, U.S.P., 4 grains. Of the fluid extract, 15 minims as a laxative. Leptandrin, 1/4 to 2 grains.