Bryonia. N. F. IV. Bryony.—The N. F. describes it as "the dried root of Bryonia alba, Linne or of Bryonia dioica Jacquin (Fam. Cucurbitaceae), without the presence of more than 5 per cent. of foreign matter. Usually in circular or elliptical slices, obtained by cutting the root more or less transversely, from 1.5 to 10 cm. in breadth and from 3 to 15 mm. in thickness; the edges light gray or yellowish, rough and. striate, the cut surface white or faintly yellow, showing a thin cortex and a wood with numerous projecting, collateral fibro-vascular bundles arranged in concentric zones; fracture short and mealy, whitish internally. Odor faint but distinct and characteristic; taste bitter and nauseous. The powdered drug is of a light yellow color and, when examined under the microscope, shows simple, rounded, or two- or more compound, starch grains from 0.004 to 0.024 mm. in diameter, frequently with a central cleft, tracheae from 0.035 to 0.25 mm. in width, reticulate or with bordered pores, and large yellow cork cells. Add sulphuric acid to the powdered drug; it becomes reddish-brown and then brownish-purple. Bryonia yields not more than 8 per cent. of ash."
The peasants are said sometimes to hollow out the top of the root, and to employ the juice which collects in the cavity as a drastic purge. (Merat and De Lens.) The berries are also purgative, and are used in dyeing. B. americana Lam. and B. africana Thunb., are respectively used in the West Indies and Africa as hydragogue cathartics in dropsy. The berries of the European black bryony (Tamus communis L.. are said to be an irritant poison, and Coutagne has found that their tincture causes in animals paralysis and convulsions. (See Rep. de Pharm., Nov., 1884; also P. J., Jan., 1903.)
Bryonia contains a glucoside, bryonin, C48H80O19, and a peculiar resin called bryoresin. According to Power and Moore (Tr. Chem. Soc., 1911, xciv), bryonin is a mixture of a glucoside and an alkaloid, neither of which is physiologically active. The activity of the plant resides in its resin. Bryonin occurs as a brownish-yellow amorphous powder of bitter taste, soluble in water and alcohol. It is used as a cathartic in hepatic congestion and in conditions following acute infectious diseases. Dose, one-sixtieth of a grain (0,001 Gm.) every two hours.
Bryonia is an active irritant hydragogue cathartic. In a number of cases it has produced serious or even fatal poisoning. Vomiting and purging have been commonly present, but in some cases there has been no diarrhea. Giddiness, delirium, and dilated pupils, coupled with fall of the bodily temperature, imperceptible pulse, cold perspiration, and other manifestations of collapse, are the usual symptoms. Eighty minims (5 mils) of the homeopathic tincture caused very serious but not fatal poisoning. (For cases, see P. J., 1858, p. 542; L. L., May 9, 1868; B. M. J., 1883, ii, 1067; T. G., ii, 35; also Woodman and Tidy.) The fresh root is highly irritant, and is said, when bruised and applied to the skin, to be capable of producing vesication. The medicine was well known to the ancients, and has been employed as a hydragogue cathartic in dropsy. Dose, ten to thirty grains (0.65-2.0 Gm.). The tincture is official in the N. F. (see Part III).