Cusso. Br. Kousso.

Botanical name: 

[Brayera]

"Kousso consists of the dried panicles of pistillate flowers of Brayera anthelmintica, Kunth." Br. "The dried panicles of the pistillate flowers of Hagenia abyssinica (Bruce) Gmelin (Fam. Rosaceae), without the presence of more than 10 per cent. of the staminate flowers, other parts of the tree, or other foreign matter. Reject any portions of the stems over 3 mm. in diameter and any binding material, before the drug is powdered or used." N. F.

Brayera, N. F.; Kooso; Kusso; Cousso, Fr. Cod.; Kousso, Fr.; Flores Koso, P. G.; Kosoblüthen, Koso, Kusso, Cusso, G.; Kousso, Cosso, It.; Couso, Sp.

Kousso was dropped from the U. S. P. IX but has been introduced into the N. F. IV and is retained in the Br. Pharm., 1914.

Hagenia abyssinica Willd. (Syn. Brayera anthelmintica Kunth) is a beautiful tree about twenty feet high, growing on the table-land of Abyssinia, at an elevation of from three thousand to eight thousand feet. The branches exhibit circular cicatrices, left by the fallen leaves. The latter are crowded near the ends of the branches, are large, pinnate, sheathing at the base, with opposite, lanceolate, serrate, leaflets, villose at the margin, and nerved beneath. The unisexual flowers are tinged with purple, pedicelled, with an involucre of four roundish, oblong, obtuse, membranous bracts, and are arranged in fours, upon hairy, flexuous, bracteate peduncles, with alternate branches. They are small and of a greenish color, becoming purple. These and the unripe fruit are the parts of the plant employed. The petals are apt to be wanting in the dried flowers. They are brought from Abyssinia packed in boxes, reaching Europe chiefly by way of Aden and Bombay. The Abyssinian name of the medicine has been variously spelled by European writers kosso, koosso, cusso, cosso, etc. The fruit of the tree is said to be used as an anthelmintic in Abyssinia, but Dragendorff failed to detect any active principle in it. It is stated that in Abyssinia, honey gathered directly after the flowering season from beehives in gardens planted with kousso plants, is used in doses of a teaspoonful as a very effective tenicide.

Properties.—The dried flowers are in unbroken though compressed clusters. The male flowers are usually collected, so that ordinarily the general color of the mass is greenish-yellow or light brown; sometimes the female flowers constitute the bulk of the drug, which then has a distinct reddish tint, and is often known in commerce as red kousso. In accordance with our Pharmacopoeia, this commercial variety should alone be used. The male flowers are often found mixed with the female flowers, when loose (not in bundles), as high as 12 per cent. of this adulteration having been noticed by Meyer and Sandlund. (Ph. Ztg., 1893, No. 99.) The description in the Br. Pharm. is as follows: "Usually in more or less cylindrical rolls from three to six decimetres long, composed of reddish panicles of pistillate flowers. Panicles mush branched, the branches arising from the axils of large sheathing bracts; more or less covered with hairs and glands. Flowers numerous, small, shortly stalked, mostly unisexual, with two roundish, membranous, veined bracts at the base of each. Calyx with reddish veins, hairy externally, and consisting of two alternating whorls each of five segments, the inner whorl being curved inwards over the young fruit and shrivelled. No marked odor; taste bitter and acrid." Br.

The N. F. describes the drug as "usually in rolls or flattened bundles from 25 to 50 cm. in length, reddish-brown, or occurring more or less loose and stripped from the larger portions of the panicles. Panicle branches cylindrical, somewhat flattened, longitudinally furrowed or wrinkled, externally light brown to yellowish, tomentose, glandular; internally, cork brownish, bast- and wood-fibers yellow, fibro-vascular bundles in wedges, pith large and yellowish-brown; nodes distinct, each with a scar or branch and subtended by a sheathing bract; internodes mostly from 1 to 2 cm. in length; flowers subtended by two ovate, reddish, pubescent and glandular bracts; pedicel short; calyx turbinate, pubescent below, subtended by four or live rigid, spreading, obovate, purple-veined bractlets which are persistent and elongated iq fruit, alternating with and larger than the five usually shriveled, reflexed calyx lobes; petals five, caducous, and usually absent in the drug; carpels two; styles exserted, stigmas broad and hairy with prominent papillae; fruit an ovoid akene about 2 mm. in diameter, enclosed by the remains of the calyx. The staminate flowers are greenish-yellow, with about twenty fertile? stamens. Odor slight; taste bitter. The powdered drug is light brown or reddish-brown and, when examined under the microscope, exhibits numerous simple, non-glandular, straight or curved hairs, up to about 1 mm. in length, with thick, strongly lignified walls, usually enlarged at the base; glandular hairs with one- to three-celled stalks, the glandular head unicellular or consisting of one or two pairs of cells; tracheae spiral, annular, scalariform, or with bordered pores, up to 0.05 mm. in width; sclerenchymatous fibers long, thick-walled, strongly lignified and with numerous, simple, oblique pores; parenchyma of pith more or less lignified and with large simple pores; fragments of epidermal tissue from the bracts and calyx with elliptical stomata up to 0.03 mm. in length; groups of thin-walled, somewhat branching parenchyma cells with large intercellular spaces; tissue from the inner surface of the pericarp consisting of numerous, elongated, porous, strongly lignified cells; calcium oxalate in rosette aggregates up to 0.04 mm. in diameter; occasionally fragments of tissue containing prisms of calcium oxalate, the latter about 0.014 mm. in length; pollen grams few, nearly spherical, from 0.025 to 0.04 mm. in diameter, with three pores. The larger branches of the panicles exhibit simple, non-glandular hairs up to about 5 mm. in length; tracheae up to 0.125 mm. in width and rosette aggregates of calcium oxalate up to about 0.075 mm. in diameter. Brayera yields not more than 9 per cent. of ash." N. F.

As the medicine, from its high price, is apt to be adulterated, it should be procured in the unpowdered state, in which the botanical characters of the flower will sufficiently test its genuineness. It has a fragrant balsamic odor, and the taste, slightly perceptible at first, becomes in a short time somewhat acrid and disagreeable. Analyzed by Wittstein, it was found to contain, in 100 parts, 1.44 of fatty matter and chlorophyll, 2.02 of wax, 6.25 of bitter acrid resin, 0.77 of tasteless resin, 1.08 of sugar, 7.22 of gum, 24.40 of tannic acid, < ? > of lignin, 15.71 of ashes, with 0.14 part of loss. It has also been studied by Clemens Willing (Ch. Cb., 1855, 224), and by Pavesi (Viertelj. f. Prak. Pharm., 1858, viii, 505) but we are chiefly indebted to Bedall, of Munich, for determining that the bitter acrid resin of Wittstein is equivalent to the taeniin of Pavesi, and for the name of kosin. This may be obtained by treating kousso repeatedly with alcohol to which calcium hydroxide has been added; the residue is boiled with water, the liquids are mixed, filtered, and distilled, and the residue treated with acetic acid, which precipitates the kosin in a white flocculent form, soon becoming denser and resin-like, and, on drying, yellowish, or, at a higher temperature, brown. The product is 3 per cent. In bulk, kosin has an odor like that of Russian leather, a persistent bitter and acrid taste, a yellowish or yellowish-white color, and an indistinct crystalline appearance under the microscope. It is very sparingly soluble in water, but freely so in alcohol, ether, and alkaline solutions. (A. J. P., 1872, 394.) Its formula, according to Flückiger, is C31H38O10. It fuses at 142° C. (287.6° F.), and remains after cooling an amorphous yellow mass, but if touched with alcohol it immediately assumes the form of stellate tufts of crystals. This may be repeated at pleasure, kosin not being altered by cautious fusion. (Pharmacog. 2d ed., 258.) Leichsenring (A. Pharm., 1894, 50) has reexamined kousso, and finds an inactive crystalline principle to which he gives the name protokosine, and an amorphous substance, kossotoxine, which he considers the active principle of the drug; the latter is a yellowish powder, fusing at 80° C. (176° F.), and not obtainable in a crystalline state. It is easily soluble in alcohol, ether, benzene, carbon disulphide, and insoluble in water.

Sodium kosinate has been recommended by Pavesi as a very eligible preparation for obtaining the virtues of kosin; a process is given in Am. Drug., 1884, 96; A. J. P., 1885.

Uses.—Kousso is highly valued in Abyssinia as a vermifuge. Bruce speaks of it in his travels, and gives a figure of the plant. Brayer, a French physician practising in Constantinople, published a treatise on it at Paris in 1823. It was in his honor that Kunth adopted the generic title of the plant. Much attention has been attracted to this valuable medicine, and trials made with it have proved its efficacy in the destruction and expulsion of the tape-worm. Its effects when taken internally are not very striking. In the ordinary dose it sometimes produces heat of stomach, nausea, and even vomiting, and shows a tendency to act on the bowels, though this effect is not always produced. It appears to act exclusively as a poison to the worms, and has been found equally effectual in both kinds of tape-worm. The medicine is taken in the morning upon an empty stomach, a light meal having been made the preceding evening. A previous evacuation of the bowels is also recommended. The flowers are given in the form of powder, mixed with half a pint of warm water, the mixture being allowed to stand for fifteen minutes, then stirred up, and taken in two or three draughts at short intervals. The medicine may be preceded and followed by lemonade. The medium dose for an adult is half an ounce (15.5 Gm.), which may be diminished one-third for a child of twelve years, one-half for one of six years, and two-thirds for one of three years. Should the medicine not act on the bowels in three or four hours, a brisk cathartic should be administered. One dose is said to be sufficient to destroy the worm. Should the quantity mentioned not prove effectual, it may be increased to an ounce (31 Gm.).

Pure kosin has been considerably used in Germany in doses of thirty grains (2 Gm.), taken in two or four powders; but Buchheim found pure kosin less powerful as an anthelmintic than that which was not pure, while Arena (Ph. Z. R., 1879, 655) believes that kosin is not the active principle at all, but that the activity of kousso resides exclusively in the green, slightly bitter resin, which is soluble in alcohol and ether. If this view be correct, it explains the greater efficacy of freshly powdered kousso, for the green resin turns yellow by age and loses its power, and Arena's investigations further indicate that the amorphous kosin of commerce is preferable to the pure principle. It is a yellowish-brown mass, which may be given in doses of from seven to fifteen grains (0.45-1.0 Gm.), repeated every half hour until four doses are taken, to be followed in an hour by a full dose of castor oil. So far as we know, no cases of poisoning by kousso or its active principle are on record, but it has been found by Rochebrune to be capable of causing centric convulsions in the lower animals.

Dose, of kousso, half an ounce (15.5 Gm.); of kosin, seven to fifteen grains (0.45-1.0 Gm.).


The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.