BOTANICAL CHARACTERISTICS.—Clammy, pubescent, foetid, narcotic annuals or biennials. Leaves clasping, sinuate-toothed, and angled. Flowers sessile, in one-sided, sessile spikes in the axils of the leaves; calyx urn-shaped; corolla dull yellow, reticulated with purple veins. Fruit a 2-celled capsule.
SOURCE.—Europe and Asia; from biennial plants growing wild or cultivated in Britain, when about two-thirds of the flowers are expanded. The plant is found in the northeastern section of the United States in wet grounds, growing in great abundance about Detroit and in other parts of Michigan.
DESCRIPTION OF DRUG.—The fresh leaf is from 2 to 10 inches long, 1 to 4 inches broad, ovate to ovate-oblong in shape. On each side 3 to 5 coarse, sinuate teeth or lobes, which are rather acute and oblong or triangular. On drying, the leaves shrivel and crumple up around the very large, light-colored midribs, and generally have the large petiole still attached; they are grayish-green, and of a coriaceous texture; leaves, in the market, are very much broken; odor heavy, narcotic; taste bitter and nauseous.
Powder.—Microscopical elements of: See Part iv, Chap. I, B.
CONSTITUENTS.—By distillation the leaves yield a very poisonous volatile oil, but the active principles are hyoscyamine, C17H23NO3 (crystalline), and hyoscine, C17H21NO4 (amorphous). They also contain about 2 per cent. of potassium nitrate, which causes them to crackle when thrown in the fire. Ash, not exceeding 30 per cent.
Preparation of Hyoscyamine from Seed.—First extract fatty matter; acidulate with HCl; evaporate; wash acid solution with benzene. Neutralize solution with NH4OH, shake out with chloroform, and evaporate latter solvent.
ACTION AND USES.—Anodyne, hypnotic, narcotic. The action of hyoscyamus is that of its alkaloid, hyoscyamine, which acts like atropine but is less irritant and more calmative and hypnotic. Hyoscine is a decided anodyne and hypnotic. The extract in the form of a suppository is frequently employed to relieve the pain of hemorrhoids, and a poultice made from the leaves may be employed to allay the pain of cancerous and other ulcers. Dose of leaves: 5 to 15 gr. (0.3 to 1 Gm.); Hyoscyamine salts, 1/100 gr. (0.0006 Gm.); Hyoscine hydrobromate (Scopolamine hydrobromate), 1/100 gr. (0.0006 Gm.).
RELATED SPECIES.—Hyoscyamus pallidus (flowers pale yellow), H. agrestis (flowers few, leaves smaller), and H. albus (flowers white). The latter is used indiscriminately in France with the niger, with which it appears to be identical in medicinal properties.
VARIETIES.—There are two varieties of henbane, the annual and biennial. The former when properly grown are not devoid of active properties. The official plant is susceptible of considerable diversity of character. causing varieties which have been considered by some as distinct species, and by cultivation differing somewhat in medical properties.
- OFFICIAL PREPARATIONS.
- Tinctura Hyoscyami (10 per cent.), Dose: 10 to 60 drops (0.6 to 4 mils).
- Fluidextractum Hyoscyami 1 to 3 gr. (0.065 to 0.2 Gm.).
- Extractum Hyoscyami 5 to 15 drops (0.3 to 1 mil).
510. HYOSCYAMI SEMEN (unofficial).—Used for the same purposes as the leaves and contain the same alkaloids, but in larger proportion, together with a large quantity of fixed oil and a bitter glucoside, hyoscyopicrin. They are small, reniform, and have a peculiar gray-brown surface, much wrinkled and finely pitted; near the raised portion of the testa they are rather sharp (distinction from stramonium seed). The embryo is curved so as to form a figure 9, the lower part of which is the radicle, and is surrounded by a whitish, oily albumen. Odorless in entire state, but when rubbed, of a distinctly narcotic odor; taste oily and bitter.