Mezereum (U. S. P.)—Mezereum.
"The bark of Daphne Mezereum, Linné, and other species of Daphne.—(U.S.P.).
COMMON NAME AND SYNONYMS: Mezereon-bark; Mezerei cortex, Cortex mezerei, Cortex thymeleae, Cortex coccognidii.
ILLUSTRATION: Bentley and Trimen, Med. Plants, 225, 226, 227.
Botanical Source.—DAPHNE MEZEREUM. Mezereon, or Spurge olive, is a weather-proof shrub, with a large root and bushy stem, 4 or 5 feet high, with upright alternate, smooth, tough, and pliant branches, leafy when young, and a smooth, dark-gray bark, which is not strongly attached to the wood. The leaves are terminal on the branches, scattered, stalked, lanceolate, smooth, deciduous, 2 inches long, appearing after the flowers, and soon accompanied by flower-buds for the next season. The flowers are highly fragrant, of a pale-rose color, in little clusters on the naked branches, with several brown, smooth, ovate bracteas underneath. Calyx tubular, hairy externally, like a corolla in texture, and crimson all over; limb in 4 deep, ovate, spreading, colored segments. Stamens 8; filaments short, in 2 rows, from about the middle of the tube; anthers roundish-oblong, 2-celled, simple, and inclosed within the tube. Ovary superior, ovate; style short and terminal; stigma capitate, depressed, and entire. The berry is scarlet, pulpy, oval, 1-celled, and 1-sided; the seed suspended, oval, and large, with a thin brittle skin (L.).
DAPHNE GNIDIUM is a small bush, with the leaves linear-lanceolate, clustered, acuminate, cuspidate, and quite smooth. The flowers are numerous, small, white, downy, and fragrant, in terminal, panicled racemes. The fruit is globular, dry, at first green, but ultimately black (L.).
DAPHNE LAUREOLA, or Spurge-laurel, is a smooth plant, with a stem 2 or 3 feet high, round, pale, brown, upright, tough, and pliant branches, crowned with tufts of evergreen leaves, elegantly drooping in all directions, about 2 or 3 inches long, lanceolate, glabrous, acute, entire and subsessile. The flowers are deep-green, with orange anthers, 4 of which are just visible in the throat of the calyx, 5 together in each axillary raceme. An oval, concave bract accompanies each short partial stalk, at the base. Berry oval and black (L).
History and Description.—All species of Daphne possess active properties, but the bark met with in commerce is usually obtained from the three above described, that from the latter being less active than the others. The D. Mezereum is a native of the northern parts of Europe, where it is cultivated both as a medicine and as an ornament; it flowers very early in the spring, often before the snow has disappeared. This species is the most active plant of the genus; its bark is generally collected in the spring. It is met with in flat or quilled pieces, a few feet in length, and from 8 to 12 lines in breadth, and put up in packages which are often globular. Alcohol takes up its virtues, also boiling water. Oils or fats boiled with it, likewise take up its active principles and form ointments. The D. Gnidium is found in the south of France on hills and barren plains, and its bark is employed equally with that of the other kinds; the root-bark is also used in medicine. The barks of the three species constitute the official drug, which is described as follows: "In long, thin bands, usually folded or rolled into disks; outer surface yellowish or brownish-yellow, with transverse scars, and minute, blackish dots, underneath of a light-greenish color; inner surface whitish, silky; bast in transverse layers, very tough; inodorous; taste very acrid"—(U. S. P.). The leaves of D. salicifolia, Kunth, of Mexico, are used in that country as an epispastic.
Chemical Composition.—The active principle of the bark of Daphne Mezereum is an acrid resin soluble in alcohol and ether, insoluble in water (Buchheim); it is probably formed by oxidation of volatile oil present in the bark. The latter also contains wax, yellow coloring matter, sugar, nitrogenous and gummy matter, malic acid and malates, and daphnin, a crystallizable odorless, neutral substance of bitter, somewhat astringent taste, discovered in 1812 by Vauquelin, in the bark of D. alpina, and by Gmelin and Bär (1822) in the bark of D. Mezereum. Zwenger (1860) found it to be a glucosid, of the formula C15H16O9+2H2O. It is but little soluble in cold water or alcohol, but readily soluble in hot water or alcohol, insoluble in ether. By boiling with diluted acids, or under the influence of certain ferments, daphnin is decomposed into sugar and daphnetin, a crystallizable body having the odor of coumarin; it was found by Stünkel (1879) to be dioxy-coumarin (C6H2[OH]2.CHCH.COO). Umbelliferon (see Galbanum), an isomer of daphnetin, was obtained by Zwenger (1854) upon dry distillation of mezereum-resin. In the fruit, A. Casselmann (Jahresb. der Pharm., 1870, p, 62) determined the presence of 31 per cent of a fatty, drying oil, 5.46 per cent ash, 0.32 per cent of an acrid resin soluble in alcohol, and 0.38 per cent of coccognin, a crystallizable substance not identical with daphnin. It is soluble in alcohol and alkalies, soluble with difficulty in hot water, insoluble in cold water and in ether. Upon being heated it sublimes with partial decomposition, the odor of coumarin being developed.
Action, Medical Uses, and Dosage.—In large doses, mezereon is an irritant poison, causing redness and vesication of the skin when left in contact with it, and causing when swallowed, dryness and burning of the throat, vomiting, hypercatharsis, and frequently renal irritation. The berries have proved fatal to children who have eaten them; yet in some countries they are used as a purgative in doses of 8 to 12. In small doses it acts as a stimulant, alterative, diuretic, diaphoretic, in warm decoction, and cathartic. It acts favorably in syphilis, mercurio-syphilis, scrofula, chronic rheumatism, and some forms of obstinate disease of the skin. Dose of the decoction, from 1 to 3 fluid ounces; of the powder, 10 grains. Homoeopathists regard it highly in the treatment of the periosteal pains and nodes following syphilitic infection, and in rheumatic, and even in syphilitic periostitis.
Externally, it is used occasionally; sometimes employed by practitioners to produce rubefaction and vesication, and in the form of ointment as an application to blistered surfaces, indolent ulcers, and issues, in order to excite suppuration. When vesication is desired, the bark is soaked in hot vinegar and water to soften it, and then applied to the part by a compress and bandage. The application is to be renewed night and morning, until vesication is produced.