Cusparia Bark. Cuspariae Cortex. Br. 1898. Angustura, U. S. 1870. Angustura (Angostura) Bark. Carony Bark. Cortex Angusturae. Angusture vraie, Fr. Cod. Angusture, Fr. Angusturarinde, G. Corteccia dell' Angustura, It. Corteza de Angostura, Sp.—"The dried bark of Cusparia febrifuga, DC." Br., 1898. This bark was dropped from the U. S. Pharmacopoeia at the revision of 1880 and from the British in 1914. The subject of Angostura bark in its botanical relations has been involved in some confusion. Humboldt and Bonpland were the first to throw light upon its true source. Unable to attach it to any known genus, they erected it into a new one with the title of Cusparia, a name of Indian origin, to which they added the specific appellation of febrifuga. On their authority, Cusparia febrifuga was generally believed to be the true source of the medicine, and was recognized as such by the London College. But it appears from the researches of Hancock, who resided for several months in the country of the Angustura bark tree, that it is doubtful whether the plant described by Humboldt and Monpland is that which yields the drug, and not another species of the same genus. Hancock proposed for the plant of the Orinoco the title of Galipea officinalis, which was adopted in the U. S. P., 1870. This name was afterward changed by Hancock to Cusparia officinalis, which is now generally accepted as the correct origin for true Angostura bark.
Cusparia febrifuga is a small tree, irregularly branched, with an erect stem from three to five inches in diameter, and covered with a smooth gray bark. The leaves are alternate, petiolate, and composed of three leaflets, which are oblong and pointed at each extremity. They are very smooth and glossy, of a vivid green color, marked occasionally with small whitish round spots, and, when fresh, of a strong odor resembling that of tobacco. The flowers are numerous, white, arranged in axillary and terminal peduncled racemes, and of a peculiar unpleasant odor. The fruit consists of five two-valved capsules, of which two or three are commonly abortive. The seeds, two of which are contained in each capsule, one often abortive, are round, black, and of the size of a pea. The tree grows abundantly on the mountains of Carony, between the 7th and 8th degrees of N. latitude, at the height of from six hundred to one thousand feet above the level of the sea.
The bark is generally brought from the West Indies packed in casks; but, according to Brande, the original package as it comes from Angostura consists of the leaves of a species of palm, surrounded by a net-work of sticks.
Cusparia bark "occurs in flattened or curved pieces, or in quills, generally about 10 to 12 Cm. long, 2.5 Cm. wide, and 2 mm. thick. The outer layer usually consists of a gray or yellowish cork which is often soft and easily removed, disclosing a hard, dark brown inner layer; the inner surface is light brown and frequently laminated. The fracture is short and resinous; on the fractured surface many white points are visible. A transverse section exhibits numerous cells filled with acicular crystals of calcium oxalate and small oil glands, but seldom any sclerenchymatous tissue other than small isolated groups of bast fibers. Odor musty; taste bitter." Br., 1898. Calcium oxalate raphides are abundant in the bark, but the most characteristic peculiarity is the presence of numerous cells a little larger than the other parenchymatous cells and completely filled with oil or a yellowish resin. The odor of Angustura bark is peculiar and disagreeable when fresh, becoming fainter with age; the taste is bitter and slightly aromatic, leaving a sense of pungency at the end of the tongue. According to Fischer, it contains volatile oil, bitter extractive, a hard and bitter resin, a soft resin, a substance analogous to caoutchouc, gum, lignin, and various salts. Oberlin and Schlagdenhauffen (1878) found in the bitter extractive an alkaloid, angosturine, C10H40O14N, which melts at 85° C. (185° F.), is crystallizable, and is turned red by pure sulphuric acid, and green by sulphuric acid with admixture of nitric acid. The volatile oil, which may be obtained by distillation with water, is of a pale yellowish color, lighter than water, of an acrid taste, and with the odor of the bark. Beckurts and Froeger (Gildemeister and Hoffman, Aetherische Oele, p. 601) found as its essential ingredient a sesquiterpene alcohol, C15H26O, to which they give the name galipol. It H17O3N. Korner), melting at 89° C. (192.2° F.) and is optically inactive. Cadinene, C15H24, is also present and gives left rotatory character to the oil. A small quantity of an inactive sesquiterpene, galipene, is also present, as well as traces of a terpene which is probably pinene. The cusparine of Saladin has not been found by other investigators. Beckurts and Nehring (A. J. P., 1892, 410) announced the discovery of four alkaloids in Angustura bark—-viz., galipine, C20H21O3.N, melting at 115.5° C. (240° F.) and crystallizing in slender lustrous needles of white color; galipidine, C19H19O3N, melting at 111° C. (231.8° F.) and crystallizing in silky lustrous plates of white color; cusparine, C20H19O3N (C19H17O3N, Korner), melting at 90° C. (192.2° F.) and readily soluble in alcohol, ether, chloroform, acetone, and benzene, more sparingly in light petroleum; and cuspardine, C19H17O3N, melting at 78° C. (172.4° F.) and crystallizing in minute slender white needles. Its salts are less soluble than those of galipine and galipidine, but more readily than those of cusparine. The four alkaloids are tertiary bases. (See also A. Pharm., 233 (1895, No. 6), 410.) Beckurts and Nehring also extracted the essential oil, amounting to 1.5 per cent. It had a sp. gr. at 15° C. (59° F.) of 0.956. Distilled under a pressure of 35 mm. it commenced to boil at 153° C. (307.4° F.) and the greater part distilled between 200° and 220° C. (392°-428° F.) the last portions becoming solid when artificially chilled. (See also A. Pharm., 1897, 518.) They found the bitter principle angosturine, which when purified was white and melted at 58° C. (136.4° F.). A glucoside was also found, the solution of which fluoresced; but it was not investigated. Troeger and Beck assert that angostura bark contains cusparine, C19H17ON3 (thus confirming Korner's formula) galapoidine, C19H15ON4, and a new alkaloid of the formula C16H13O2N. (A. Pharm., 1913, ccli, 246.) For a description of false Angustura barks, see U. S. D., 19th ed., p. 417.
Angustura bark has long been used by the natives of South America and the West Indies as a stimulant tonic. In large doses it also evacuates the stomach and bowels, and is often employed for this purpose in South America. It is said to be peculiarly efficacious in bilious diarrheas and dysenteries, and has been recommended in dyspepsia and other diseases requiring a tonic treatment. The testimony, however, of practitioners in Europe and the United States, is not strongly in its favor.
The Br., 1898, Infusion of Cusparia was prepared as follows: "Cusparia Bark, in No. 20 powder, 1 ounce (Imperial) or 5.0 grammes; Distilled Water, boiling, 1 pint (Imp. meas.) or 1000 mils. Infuse in a covered vessel for fifteen minutes; strain." Br., 1898. Under the name of Infusum Angusturae this preparation was official in the U. S. Pharm., 1870, made in the proportion of half a troyounce of Angustura bark in a pint of water. Dose, two fluidounces (60 mils), repeated every two, three, or four hours.
It may be given in powder, infusion, tincture, fluidextract, or extract. Dose, of the extract, five to fifteen grains (0.32 to 1 Gm.), which, however, according to Hancock, is inferior to the powder or infusion. To obviate nausea, it is frequently combined with aromatics. Dose, in substance, ten to thirty grains (0.65 to 2.0 Gm.). In larger quantities it is apt to produce nausea. It is known best in the proprietary preparation called "Angustura Bitters."