Pareira. N. F. IV (U. S. P. VIII, Br. 1898). Pareira Brava, Pareira Radix, Br. Pareira Root.— "The dried roots of Chondrodendron tomentosum Ruiz and Pavon (Fam. Menispermaceae) without the presence of more than 5 per cent. of stems or other foreign matter." N. F.
Chondrodendron tomentosum is a climbing, woody vine, which attains often a considerable height, and is remarkable for the size of its leaves. These are about a foot long, broadly ovate or rounded, slightly cordate, with a smooth upper surface, and on the under surface, between the veins, covered with a fine close wool of an ashy hue. The racemose fruits are of the size of large grapes, oval and black. This plant inhabits both Brazil and Peru.
Pareira was formerly official in the U. S. VIII and Br. Pharmacopoeias, but is now official in the N. F. IV, where it is described as follows: "Nearly cylindrical, more or less tortuous, of variable length and from 1 to 6 cm. in diameter. Externally brownish-black or blackish-brown with transverse ridges on knot-like projections, occasionally fissured and longitudinally wrinkled or even furrowed. Hard, heavy and tough; when freshly cut having a waxy luster; the transverse surfaces exhibiting several successive eccentric and distinctly radiate concentric zones of projecting, secondary fibro-vascular bundles, each from 2 to 4 mm. in width, and separated by distinct concentric zones of parenchyma and stone cells. Stem deeply furrowed, grayish in color, usually covered with foliaceous patches of lichens bearing their blackish apothecia; internally grayish-yellow, with a prominent development of wood with a tendency to separate fibro-vascular bundles and without a waxy luster. Odor slight, taste very bitter.
The powder is dark brown, containing numerous starch grains and a few woody fragments; starch grains mostly simple, occasionally unequally two-to four-compound, the individual grains ellipsoidal or oblong, 0.005 to 0.02 mm. in diameter and occasionally with central clefts or irregular markings; fragments with large, wide tracheae, the walls with numerous slit-like pores and associated with long, thick-walled, strongly lignified, porous wood fibers; stone cells in small groups, with thick porous walls and in form resembling those of the fruits and seeds; fragments of starch-bearing parenchyma; the cells of the root being thick-walled, strongly lignified and with large, longitudinal, elliptical pores; occasional fragments of blackish-brown cork. Pareira yields not more than 5 per cent. of ash." N. F.
For account of commercial history, see U. S. D., 18th ed., 1916.
The root imparts its virtues readily in water. Feneuille found in it a soft resin, a yellow bitter principle, a brown substance, a nitrogenous substance, fecula, acid calcium malate, potassium nitrate, and various other salts. He considers the yellow bitter substance as the active principle. It is soluble in water and alcohol, and precipitated from its solution by tincture of galls. Wiggers announced in 1838 the existence in pareira brava of an alkaloid, for which he proposed the name of pelosine or cissampeline. Peretti of Rome, and Pelletier afterwards, separated from the root an alkaloid characterized by assuming a beautiful purple color upon contact with strong nitric acid. (J. P. C., xxvi, 162.) It is stated to be uncrystallizable, insoluble in water, soluble in ether, alcohol, and the acids, and of an intensely bitter and sweetish taste. Fluckiger (P. J., 1870, p. 192) found an alkaloid in pareira, and, having thoroughly determined its origin, investigated its properties, and fixed its composition at C18H21NO3, showed its identity with the bebeerine of nectandra and the buxine of Buxus sempervirens obtained by Walz. Ringer and Brooke (A. J. P., 1892, 255) proved that the true chondrodendron root contained a larger quantity of chemical and extractive principles than do the substitutes. (See also Dohme's paper, D. C., 1896, 296.)
Pareira is supposed to have a diuretic effect and to act as an antiseptic in the bladder. It is chiefly employed for the relief of chronic inflammations of the urinary passages. In Brazil it is used in the cure of the bites of poisonous serpents, —a vinous infusion of the root being taken internally, while the bruised leaves of the plant are applied to the wound. The dose of pareira in substance is from thirty grains to a drachm (2.0-3.9 Gm.). The infusion (1 oz. in 1 pint of boiling water) is useful. The aqueous extract may be given in the dose of from ten to thirty grains (0.65-2.0 Gm.). There is an official fluidextract made with diluted alcohol in the N. F. IV.
For preparations of pareira see U. S. D., 19th cd., p. 917.
Dose, thirty to sixty grains (2.0-3.9 Gm.).
The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.