Colocynth pulp or bitter apple (Colocynthis, U.S.P.; Colocynth) is obtained from the fruit of Citrullus Colocynthis, Schrad. (N.O. Cucurbitaceae), a plant distributed throughout North Africa, Syria, Persia, and North-West India, and cultivated in Spain and Cyprus. The fruit is collected when ripe, freed from the rind and dried. More rarely it is imported unpeeled. The drug occurs in commerce in balls about 5 centimetres in diameter, which are often more or less broken. Each fruit consists of a whitish, pith-like pulp, in which a large number of hard, whitish or brownish, flattened, oval seeds, arranged in six vertical rows, are contained. For use in pharmacy the pulp must be separated from the seeds by breaking the fruits open and picking or sifting. The pulp thus obtained has little odour but an intensely bitter taste; the seeds, when quite free from adhering pulp, are almost tasteless. Colocynth pulp consists of very large, thin-walled, parenchymatous cells, with occasional fibro-vascular bundles, which are accompanied by tubular cells containing the active constituent colocynthin. On incineration, from 7 to 13 per cent. of ash is obtained (B.P., at least 9 per cent.). Two varieties, Turkey colocynth and Spanish colocynth, are regularly imported. Of these the former is the finer fruit, and more esteemed, as it is whiter in colour and contains a larger proportion of pulp. The seeds, which form about 75 per cent. of the weight of the drug as imported, consist of a hard shell enclosing a small, oily nucleus; they yield from 2.5 to 3 per cent. of ash, and contain about 15 percent. of fixed oil. The presence of seeds in powdered colocynth would increase the amount of oil yielded to petroleum spirit, which should not exceed 2 per cent. Petroleum spirit is preferable to ether, which is specified in the B.P. test; ether removes about 3 to 3.5 per cent. from the dried pulp, but only about one-third of this is oil. More definite information concerning the presence of the seeds is afforded by microscopical examination, by which the sclerenchymatous tissue of the seed-coats may readily be detected. The presence of starch in the powdered drug would be revealed by the iodine test.
Constituents.—Colocynth pulp contains the bitter, amorphous, purgative alkaloid, colocynthine, and an amorphous non-basic purgative principle or principles; it also contains a small amount of an amorphous glucosidic substance, and the following substances which are physiologically inactive:—α-elaterin, citrullol, hentriacontane, a phytosterol, and a mixture of fatty acids. The seeds contain about 15 per cent. of fixed oil, traces of an alkaloid, a phytosterol, and an enzyme which hydrolyses β-glucosides.
Action and Uses.—Colocynth pulp is a powerful hydragogue cathartic; it is rarely used alone, on account of its drastic nature, but is an important ingredient in Extractum Colocynthidis Compositum, Pilula Colocynthidis Composita, and Pilula Colocynthidis et Hyoscyami. It is extremely irritant, severe pain being caused if the powdered drug be applied to the nostrils. A simple tincture of colocynth is prepared. It has a nauseous, bitter taste; but may be given in mixture form with the tinctures of podophyllum and belladonna. Colocynth fruits, broken small, are much used for keeping away moths from furs and woollen goods. In cases of poisoning by colocynth, the stomach should be emptied, opium given by mouth or rectum, followed by stimulants and demulcent drinks.
Dose. 1 to 3 decigrams (2 to 5 grains).
- Extractum Colocynthidis, U.S.P.—EXTRACT OF COLOCYNTH.
- Colocynth pulp, 100; alcohol (49 per cent.), a sufficient quantity. The colocynth is first macerated with some of the alcohol and the liquor expressed, and then percolated with a further quantity until 500 in all is obtained. The strained and mixed liquids are evaporated to dryness and the residue reduced to powder, Average dose.—30 milligrams (1/2 grain).
- Extractum Colocynthidis Compositum, B.P.—COMPOUND EXTRACT OF COLOCYNTH. Syn.—Extractum Catharticum.
- Colocynth Pulp, 30; extract of Barbados aloes, 60; scammony resin, 20; curd soap, in shavings, 20; cardamom seeds, in very fine powder, 5; alcohol (60 per cent.), 800. Prepare a tincture of colocynth by macerating the drug with the alcohol for four days; then remove the alcohol by evaporation, add the extract, resin, and soap, and evaporate the mixture to a firm extract, adding the cardamoms near the end of the operation. Compound extract of colocynth is commonly kept for dispensing purposes in the form of powder, 5 parts of powder approximately representing 6 parts of mass. It is usually prescribed with extract of henbane or extract of belladonna to prevent griping; it forms with calomel or blue pill the basis of most "antibilious pills." The powdered extract is best massed with a trace of diluted alcohol. Dose.—1 to 5 decigrams (2 to 8 grains).
- Extractum Colocynthidis Compositum, U.S.P.—COMPOUND EXTRACT OF COLOCYNTH, U.S.P.
- Extract of colocynth, 16; purified aloes, 50; cardamom, in No. 60 powder, 6; scammony resin, 14; hard soap, 14; alcohol (95 per cent.), 10. The aloes is melted on a water-bath; and the alcohol, colocynth, and scammony are then added and the mixture heated at a temperature not exceeding 120° until homogeneous, and sets to a brittle mass when cooled. The heat is withdrawn, the cardamom incorporated, and the product reduced to a fine powder. Average dose.—5 decigrams (7 1/2 grains).
- Pilula Colocynthidis Composita, B.P.—COMPOUND PILL OF COLOCYNTH. Syn.—Pilulae Cocciae; Pill Cochia.
- Colocynth pulp, in powder, 18; Barbados aloes, in powder, 36; scammony resin, in powder, 36; potassium sulphate, in fine powder, 4.5; oil of cloves, 4.5; distilled water, a sufficient quantity. Mix the colocynth pulp with the oil previously triturated with the potassium sulphate; add the aloes and resin, mix intimately, and use sufficient water to form a mass. Dose.—4 to 8 grains. Dr. Gregory's pill consisted of 5 grains of this pill mass, prepared with scammony instead of scammony resin; Alexander's Liver Pill contained colocynth pulp, 16; Barbados aloes, 8; Socotrine aloes, 24; scammony, 24; potassium sulphate, 4; oil of caraway, 3; and rectified spirit, sufficient to make a mass.
- Pilula Colocynthidis et Hyoscyami, B.P.—PILL OF COLOCYNTH AND HYOSCYAMUS.
- Compound pill of colocynth, 2; green extract of hyoscyamus, 1. Dose.—4 to 8 grains. Christison's Pill consisted of 2 grains of this pill mass, prepared with compound pill of colocynth containing scammony instead of scammony resin. Hamilton's Pills contained compound extract of colocynth instead of compound pill of colocynth, and 90 grains of the mass was divided into 24 Pills.
- Pilulae Catharticae Compositae, U.S.P.—COMPOUND CATHARTIC PILLS.
- Compound extract of colocynth, U.S.P., 8 grammes; calomel, 6 grammes; jalap resin, 2 grammes; gamboge, 1.5 grammes; alcohol (49 per cent.), a sufficient quantity. To make 100 pills. Average dose.—2 pills.
- Pilulae Catharticae Vegetabiles, U.S.P.—VEGETABLE CATHARTIC PILLS.
- Compound extract of colocynth, U.S.P., 6 grammes; extract of hyoscyamus, U.S.P., 3 grammes; jalap resin, 2 grammes; extract of leptandra, 1.5 grammes; podophyllin resin, 1.5 grammes; oil of peppermint, 0.8 mil; alcohol, (49 per cent.), a sufficient quantity. To make 100 pills. Average dose.—2 pills.
- Pilulae Colocynthidis et Hydrargyri, B.P.C.—COLOCYNTH AND MERCURY PILLS. Syn.—Abernethy's Pills.
- Compound extract of colocynth, 2 grains; mercury pill, 3 grains; in each pill. Dose.—1 or 2 pills.
- Pilulae Colocynthidis et Hydrargyri Compositae, B.P.C.—COMPOUND COLOCYNTH AND MERCURY PILLS.
- Compound pill of colocynth, 1/2 grain; mercury pill, 1/4 grain; green extract of hyoscyamus, 1/4 grain; in each pill. Dose.—1 to 4 pills.
- Tablettae Colocynthidis Compositae, B.P.C.—COMPOUND COLOCYNTH TABLETS.
- Each tablet is approximately equal to 3 decigrams (5 grains) of the corresponding pill mass. Dose.—1 or 2 tablets.
- Tinctura Colocynthidis, B.P.C.—TINCTURE OF COLOCYNTH. 1 in 10.
- A drastic purgative and should be prescribed with carminatives to lessen the tendency to gripe. Dose.—1/2 to 1 mil (8 to 15 minims).
The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.