Hemp

HEMP (Cannabis), an annual dioecious plant of the family Cannabinaceae, order Urticiflorae (nettle), 30–150 cm tall; female specimens are taller than males and more densely covered with leaves. The stem is erect, rough from the short hairs covering it. Leaves are opposite, with a long petiole, palmately compound, covered with hairs on both sides, with 5 or 7 lanceolate leaflets and two free stipules, the terminal ones being either entire or with 3 leaflets. Male inflorescences, panicles, sit at the top of the stem and upper branches in the form of a plume, on the lower ones in the form of a curl; flowers have 5 free sepals and 5 stamens. Female inflorescences are compressed-spike-like, sit in the leaf axils and are tightly surrounded by bracts; the pistil has two large purple-red stigmas. The fruit is a nut 3–5 mm long, 2 mm wide with a thin, brittle shell of dark gray, shiny color. The original homeland of H. is considered to be Persia, where it was found in a wild state (Engler); according to another opinion, the ancestral home of H. is India. In botany, only one species of H. is distinguished—Cannabis sativa; the Cannabis indica distinguished in medicine has such insignificant morphological differences that it cannot be recognized as a separate species. The main distinguishing feature of Indian H. is its rich content of resinous physiologically active principles, which are present only in insignificant amounts in ordinary H., a result of different cultivation: in one case, they strove to obtain a plant with a large content of these principles, in the other—a plant rich in fibers. Ordinary H. is cultivated in all countries of the temperate zone mainly for obtaining hemp fiber, which goes into the manufacture of ropes, canvas, etc., and in the USSR also for obtaining seeds, which provide oil. Hemp seeds—Fructus Cannabis—contain besides 30–32% fatty oil, protein substances (about 25%), non-nitrogenous extractive substances (about 20%), wood (15%), glucose (1.5%), resin (0.3–1.6%), and ash (4–7%). Hemp seeds are used for medical purposes for the preparation of emulsions and as a component of certain mixtures, but mainly they go to obtain oil from them. Hemp oil, Oleum Cannabis, is a fairly viscous liquid; freshly pressed has a green color due to the admixture of chlorophyll, which is easily destroyed by bleaching or prolonged boiling, resulting in a more viscous oil of golden-yellow color. Hemp oil belongs to the drying oils, because it is capable of hardening by absorbing O₂ from the air, on which its application for the preparation of oil paints is based. It solidifies at -27°, beginning to cloud at -15°; its specific gravity is 0.925–0.931; saponification number is 193; iodine number is 143–158. Its constituent parts are triglycerides of unsaturated acids: linoleic—C₁₈H₃₂O₂, linolenic—C₁₈H₃₀O₂, oleic—C₁₈H₃₄O₂ and in small amounts (about 5%) palmitic—C₁₆H₃₂O₂. Hemp oil is used in the USSR in some localities for food, but in large quantities it serves technical purposes (olive oil, oil paints) and, like other cheap varieties of liquid fats, goes into the preparation of commercial liquid soap—Sapo kalinus venalis. Indian H., Cannabis indica, is cultivated in India, Southern China, Central Asia, and in Africa, especially in Egypt. Its culture in the southern states of North America gives plants possessing the same physiological action. In recent years, experiments were made to grow it in botanical gardens in Germany, and it was possible to obtain plants with a significant content of physiologically active principles. Preparations made from Indian H. in the countries producing it, designated by the general name hashish, bear various local names there: Haschisch, Ganjah, Charas, Majun, Momeca, etc. (see Hashish). The question of the active principles of hashish has not yet been finally elucidated: the substances isolated from it by various researchers—cannabine, tetanocannabine, or tetany, oxykannabine, cannabinine, cannabino, cannabindone—possess different actions, and some of them—cannabino, cannabindone, and cannabino— are even considered identical to each other. At present, cannabino is considered the active principle of hashish, belonging to phenol-aldehydes HO₂₀H₂₈CHO according to its chemical nature. It is very unstable, since it undergoes oxidation already in the air, losing in its action. For medical purposes, Indian H. began to be applied in Europe only from the beginning of the 19th century, but among the native population of eastern countries it is used in the form of hashish as an intoxicating narcotic substance since time immemorial. Preparations of Indian H. are used as hypnoticum, sedativum, and antispasmoticum; the external application recommended sometimes as a local anesthetic in neuralgic, rheumatic, etc. pains can hardly exert action. At present, the application of Indian H. and its preparations, especially in the USSR, is very limited, since, not having advantages over other hypnotics and sedatives, they possess disadvantages: firstly, prolonged use of them can create a habit to hashish; secondly, preparations of different origin are so different in strength of action that, for example, the American pharmacopoeia requires testing Indian H. by biological assay (a dose of liquid extract of 0.1 per 1 kg of weight must cause discoordination in an adult dog). Patented preparations require very careful application to avoid signs of poisoning, which was observed in individual cases. Preparations. Herba Cannabis indicae, Summitates Cannabis, herb of Indian H. (Ph VII)—dried and resin-glued parts of female plants: tops of stems, terminal leaves, flowers, and unripe fruits; serves for the preparation of other preparations. Internally (rarely) in powders or pills and for smoking in asthma 0.05–0.1–0.2 (!) pro dosi, 0.6 (!) pro die. Tinctura Cannabis b. ind. (Ph VII) is a transparent yellow-brown-green liquid, giving a strong turbidity with water; internally 6–30 drops up to 1.25 (!) pro dosi, 3.75 (!) pro die. Extractum Cannab. ind. (Ph VII) is a thick extract of dark green color, easily soluble in alcohol and ether; 0.03–0.1 (!) pro dosi, 0.3 (!) pro die in powders and pills. Indo-pal tablets from Indian H. and veronal, little used. Cannabinum is a brown powder, insoluble in water, easily soluble in alcohol, ether, chloroform; 0.05–0.1 pro dosi. Cannabinol, Cannabinon, Cannabin-done is a thick transparent liquid, easily soluble in alcohol, ether, chloroform, and nitrobenzene. It is used very rarely in doses of 0.03–0.05–0.1.