Conii Folia, B.P. Conium Leaves. Conii Fructus, B.P., Coniina.

CONII FOLIA, B.P.
CONIUM LEAVES.

Conium or hemlock leaves are obtained from the hemlock, Conium maculatum, Linn. (N.O. Umbelliferae), a plant distributed throughout Europe and Great Britain. The fresh leaves and young branches are collected when the fruit is beginning to form. The leaves are much divided and quite glabrous, the ultimate divisions terminating in smooth, colourless points. They are attached by amplexicaul petioles to a smooth hollow stem, marked with purplish spots. The inflorescence is a compound umbel, provided with both general and partial involucres, the latter consisting of three short lanceolate bracts directed outwards. The fruits bear crenate ridges, and have a deeply grooved endosperm. The drug has a disagreeable odour of mice, which is accentuated by the addition of solution of potassium hydroxide. Conium leaves are liable to adulteration with the leaves of other indigenous umbelliferous plants, such as wild chervil, Anthriscus sylvestris, Hoffm., and fool's parsley, Aethusa Cynapium, Linn.. Wild chervil is distinguished by its hairy leaves; fool's parsley by the absence of a general involucre of bracts, the bracts of the partial involucre being long and narrow, and the ultimate divisions of the leaves terminate in short brownish points.

Constituents.—The chief constituents of conium leaves are the alkaloids coniine (conine) and conhydrine; the stem contains about 0.06 per cent. of total alkaloids, the leaves about 0.18 per cent., and the flowers and flower-stalks about 0.24 per cent. Conium also contains methyl-coniine, ethyl-piperidine, and pseudo-conhydrine. Coniine is a highly toxic, colourless, oily liquid with a disagreeable mouse-like odour.

Action and Uses.—Fresh conium herb is employed in the preparation of Succus Conii, and of the green extract. Succus Conii is used internally for its sedative and antispasmodic properties (see Coniina). Externally, as Unguentum Conii, it is a soothing application to haemorrhoids and other painful or irritable conditions of the rectum and anus. For inhalation the addition of alkali to the juice is necessary to set free the alkaloid from its natural combination (see Vapor Coniinae). The green extract of conium is used in pill form and also in suppositories as a sedative. The latter may contain 30 centigrams (5 grains) in each, and require the same precaution in making as suppositories of other green extracts. Incompatible with alkalies, and preparations of conium should not be prescribed with alkalies except when intended for inhalation. In cases of poisoning by conium, the antidotes described under Coniina should be employed.

Dose.—1 to 5 decigrams (2 to 8 grains).

PREPARATIONS.

Extractum Conii, B.P., 1885.—EXTRACT OF HEMLOCK.
Press out the juice from bruised conium leaves, heat it to 54°, and strain through calico to remove the chlorophyll. Heat the strained liquor to 93°, remove the coagulated albumin by filtration, evaporate the filtrate to a thin syrup by the heat of a water-bath, add the previously separated chlorophyll, after passing it through a hair sieve, stir, and evaporate to a soft extract at a temperature not exceeding 60°. The alkaloidal content of this extract varies considerably, averaging about 0.4 per cent. It is used as a mild sedative and antispasmodic in pill form (see Pilula Conii Composita), and in suppositories, 30 centigrams (5 grains) in each, in place of Extractum Belladonnae. Dose.—1/2 to 2 1/2 decigrams (1 to 4 grains).
Pilula Conii Composita, B.P. 1885.—COMPOUND PILL OF HEMLOCK.
Extract of hemlock, 5; ipecacuanha, in powder, 1; treacle, a sufficient quantity. Dose.—3 to 6 decigrams (5 to 10 grains).
Succus Conii, B.P.—JUICE OF CONIUM. Syn.—Hemlock juice.
Juice of conium is prepared by subjecting the bruised, fresh leaves and young branches of Conium maculatum, Linn., to pressure, adding to the expressed juice one-third its volume of alcohol, allowing the mixture to stand for seven days, and filtering. This juice varies considerably in strength, different samples yielding from 0.012 to 0.062 per cent. of total alkaloidal hydrochlorides. It is used chiefly to make Unguentum Conii and Vapor Coniinae. For both preparations the standardised liquid extract of conium fruit would be more suitable. Dose.—4 to 8 mils (1 to 2 fluid drachms).
Unguentum Conii, B.P.—CONIUM OINTMENT. Syn.—Hemlock Ointment.
Juice of conium, 200; hydrous wool fat, 75. Concentrate the juice of conium to 25 by evaporation on a water-bath, at a temperature not exceeding 60°; then incorporate the hydrous wool fat. A much more satisfactory preparation can be made by evaporating 200 of conium juice to 50, and mixing it with 50 of anhydrous wool fat. A preparation more constant in strength might be prepared from the standardised liquid extract of conium fruit. Conium ointment is applied to relieve the pain of haemorrhoids, cancer, and anal fissure.
Vapor Coniinae, B.P., 1885.—CONIINE INHALATION.
Juice of conium, 4; solution of potash, 1; distilled water, 8. Mix the juice of conium and solution of potash, and add the water. Quantity sufficient for one inhalation, 12 decimils (1.2 milliliters) (20 minims), which is placed on a sponge in a suitable apparatus so that the vapour of hot water passing over it can be inhaled. Coniine inhalation is used to relieve cough in bronchitis, whooping cough, etc.

CONII FRUCTUS, B.P.
CONIUM FRUIT.

Conium or hemlock fruit is the product of the hemlock, Conium maculatum, Linn. (N. O. Umbelliferae), a plant distributed throughout Europe and Great Britain. The fruits are officially directed to be collected when full grown, but before they ripen, and dried. Conium, U.S.P., should contain not less than 0.5 per cent. of coniine. Conium fruit should be greenish-grey in colour, about 3 millimetres in length and breadth; the fruits are broadly ovoid in shape, slightly compressed laterally and crowned with small stylopods. The separate mericarps are quite glabrous and marked with five irregular crenate primary ridges. Cut transversely the endosperm is seen to be deeply grooved, but no vittae are present. The fruits have no marked odour or taste, but develop a strong disagreeable mouse-like odour when triturated with solution of potassium hydroxide.

Constituents.—If gathered at the right time and dried, hemlock fruits yield as much as 2.77 per cent. of coniine. Commercial fruits only yield from 0.5 to 1.3 per cent. of coniine, due to their collection after they have attained full growth and are ripening, at which period the quantity of alkaloid rapidly diminishes. Conhydrine, methyl-coniine, ethyl-piperidine, and pseudo-conhydrine are also present.

Action and Uses.—Conium fruit is the chief source of coniine, of which it contains a greater proportion than the leaves. Preparations of conium fruit are Tinctura Conii and Extractum Conii Liquidum, used internally as sedatives and antispasmodics (see Coniina). Unstandardised preparations of conium vary greatly in strength, but the liquid extract of conium is adjusted to contain 1 per cent. of alkaloidal hydrochlorides, thus forming a preparation of uniform potency. Incompatible with alkalies, and preparations of conium should not be prescribed with alkalies, except when intended for inhalation. In cases of poisoning by conium, the antidotes described under Coniina should be employed.

PREPARATIONS.

Extractum Conii Liquidum, B.P.C.—LIQUID EXTRACT OF CONIUM. Syn.—Liquid Extract of Hemlock.
Contains 1 per cent. of alkaloidal hydrochlorides, and is the most uniform preparation of conium. It may be used with advantage in place of the tincture and juice of conium; 1 fluid drachm (4 mils) of the liquid extract is about equal to 1 fluid ounce (30 mils) of the juice. Dose.—3 to 10 decimils (0.3 to 1.0 milliliters) (5 to 15 minims).
Fluidextractum Conii, U.S.P.—FLUIDEXTRACT OF CONIUM.
Conium fruit, in No. 40 powder, 100; acetic acid (36 per cent.), 2; alcohol (49 per cent.), sufficient to produce a liquid containing 0.45 per cent. w/v of coniine. Average dose.—2 decimils (0.2 milliliters) (3 minims).
Tinctura Conii, B.P.—TINCTURE OF CONIUM. Syn.—Tincture of Hemlock.
Conium fruit, recently reduced to No. 40 powder, 20; alcohol (70 per cent.), sufficient to produce 100. Prepare by the percolation process. Tincture of conium is used as a sedative in spasmodic affections of the respiratory organs. It has also been used as an inhalation to allay bronchial spasm. Dose.—2 to 4 mils (1/2 to 1 fluid drachm).
Unguentum Extracti Conii, B.P.C.—CONIUM EXTRACT OINTMENT.
Liquid extract of conium, 10; wool fat, 90.

CONIINA.
CONIINE.

C8H17N = 127.46.
Synonyms.—Conine; Conicine; Cicutine.

Coniine, or α-propyl - piperidine, C5H9(C3H7)NH, is a liquid alkaloid found in all parts of the hemlock, Conium maculatum, but more especially in the immature fruit, in combination with malic acid. It may be obtained by distilling the crushed seeds with weak solution of potassium hydroxide over a steam-bath, neutralising the distillate obtained with hydrochloric acid, evaporating the solution to dryness, adding excess of potassium hydroxide to the alkaloidal salt, extracting the base thus liberated with ether, and finally purifying by distillation in a current of hydrogen. By the action of sodium on an alcoholic solution of allyl-pyridine, which is a liquid product of the action of paraldehyde on picoline, coniine may be prepared synthetically. Coniine occurs in the form of an almost colourless liquid with a penetrating mouse-like odour and an acrid taste; it is volatile and dextrorotatory, and becomes brown on exposure to the air. The aqueous solution has an alkaline reaction. The base takes up 25 per cent. of water, and the cold saturated solution becomes turbid on warming. Specific gravity, 0.890. Boiling-point 166°. On cooling, it congeals to a crystalline mass, which melts at -2°. It is a powerful base, and unites with acids to form stable crystalline salts. With concentrated sulphuric acid it gives first a blood-red, and then green, colour. Potassium cadmium iodide yields an amorphous precipitate, thus distinguishing it from nicotine, which yields a crystalline precipitate. Solution of coniine is not precipitated by platinic chloride, but solutions of nicotine are. A further distinguishing test is to add 1 drop of a concentrated alcoholic solution of phenolphthalein to a solution of either base; with coniine a red colour is developed, but with nicotine there is no reaction.

Soluble in water (1 in 100) in alcohol, ether, chloroform, benzene, amyl alcohol, or acetone, but only slightly soluble in carbon bisulphide.

Action and Uses.—Coniine depresses the medulla and the motor nerve endings, so that after large doses death results from respiratory paralysis, which is mainly central—that is, the medulla is paralysed before the nerves. On the circulatory system coniine acts very like nicotine, in that it paralyses autonomic nerve-cells, after an initial stimulation, and so lowers blood pressure from paralysis of the splanchnics, and quickens the heart from paralysis of the vagi. It has been used in chorea, mania, paralysis agitans, tetanus, and strychnine poisoning for its depressant action on the motor nerves, but in this respect it is inferior to curare. In spasmodic affections such as laryngismus, whooping cough, and asthma, it is also employed. To allay cough and bronchial spasm it is best given as an inhalation. Externally, it is sedative, and especially valuable in pruritis ani and to relieve the pain of fissures, ulcerated haemorrhoids, etc. The pure alkaloid is rarely administered, coniine hydrobromide or hydrochloride being preferred. Pessaries containing 3 centimils (0.03 milliliters) (1 minim) or more of coniine in each are prepared with a glyco-gelatin basis. In cases of poisoning by coniine or its salts, the gelatin stomach should be emptied, stimulants and warmth applied, with artificial respiration if necessary. As an antidote, give strong tea or 1 to 1 1/2 grammes (15 to 20 grains) of tannic acid in aqueous solution.

Dose.—1 to 10 milligrams (1/64 to 1/6 grain).


The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.