Echinacea. N. F. IV. Nigger-head. Sampson-root. Pale Purple Cone-flower.—"The dried rhizome and roots of Brauneria pallida (Nuttall) Britton (Echinacea angustifolia De Candolle. (Fam. Compositae)." N. F. IV. This composite plant, a native of the prairie region of America west of Ohio, has been introduced by the so-called eclectic physicians as a remedy in divers dissimilar diseases. The root is described by the N. F. as "nearly entire, cylindrical, very slightly tapering and sometimes slightly spirally twisted, from 10 to 20 cm. in length and from 4 to 13 mm. in diameter, externally grayish-brown, light brown or purplish-brown, slightly annulate in the upper portion, with occasional V-shaped stem scars, somewhat longitudinally wrinkled, or furrowed; fracture short, fibrous, bark less than 1 mm. in thickness, wood thick and composed of alternate light yellowish and black wedges; the rhizome with a circular pith. Odor faint, aromatic; taste sweetish, followed by a tingling sensation suggesting aconite, but lacking the persistent and benumbing effect produced by that drug. Under the microscope, sections show the presence of intercellular (schizogenous) oil and resin cavities or reservoirs in both the wood and bark, numerous stone cells distinguished by the presence of a blackish, resinous substance in the intercellular spaces between them and some of the adjoining parenchyma, the latter containing masses or aggregates of inulin. The walls of the tracheae or vessels are marked with simple slit-like pores or annular and reticulate thickenings; bast fibers occur in the stem, and in some specimens true libriform or wood fibers are found. Echinacea yields not more than 6 per cent. of ash." N. F. Kraemer and Sollenberger (A. J. P., 1911, p. 315) have described the physical characteristics of the drug. Lloyd (Eclectic Med. Journ., 1897) obtained minute quantities of an inert alkaloid and believed that the active substance was a resin. Heyl and Hart (J. Am. C. S., 1915, xxxvii, p. 1769) found the drug to contain inulin, 5.9 per cent.; inuloid, 6; sucrose, 7; laevulose, 4; betaine, 0.1, and resins, 1.9 per cents.; the latter consisting of two isomeric phytosterols, phytosterolin, and the following fatty acids, oleic, linolic, cerotic and palmitic, but could find no physiologically active substance. Echinacea has been attributed with the property of increasing the resistance of the body to infection and is consequently used in boils, septicemia, cancer, and other infective conditions. It is also attributed with aphrodisiac and analgesic powers, but is probably without therapeutic value. The recommended dose of the fluidextract is from ten to thirty minims (0.6-1.8 mils). Hale (Lancet Clinic, March, 1901) injects an extract into the rectum in the treatment of hemorrhoids.
Brauneria purpurea D.G. Britton (Rudbeckia purpurea L., Echinacea purpurea Moench), Black Sampson, Purple Cone-flower (Virginia to Illinois and southward to Louisiana), has similar properties to B. pallida, and is similarly used.