Related entry: Aloin
Synonyms.—Barbados, Curaçao, Socotrine, Zanzibar, and Cape Aloes.
Aloes (Aloe Barbadensis, B.P., Aloe Socotrina, B.P., Aloe, U.S.P.) consists of the liquid exuded from the leaves of various species of Aloe (N.O. Liliaceae), evaporated to dryness. The leaf of the aloe plants is very fleshy and contains, near the epidermis, a row of fibrovascular bundles, the pericyclic cells of which are much enlarged and filled with a yellow juice, which exudes when the leaf is cut. This juice is collected and concentrated, either by spontaneous evaporation, or, more generally, by boiling until it solidifies on cooling; it is then poured into boxes or other convenient receptacles. The manner in which the evaporation is conducted has a marked effect on the appearance of the aloes, slow and moderate concentration tending to induce crystallisation of the aloin, thus causing the drug to appear opaque. Such aloes is termed "livery" or "hepatic," and splinters of it exhibit minute crystals of aloin, when examined under the microscope. If, on the other hand, the evaporation is carried as far as possible, the aloin does not crystallise, and small fragments of the drug appear transparent; it is then termed "glassy, vitreous," or "lucid" aloes, and exhibits no crystals of aloin under the microscope. The chief varieties of aloes are Curaçao (Barbados), Socotrine (Zanzibar), and Cape. Other varieties of aloes (such, for instance, as black "Mocha" aloes) occasionally find their way to the London market. Natal aloes is no longer a commercial article. Uganda aloes, imported from Mossel Bay (not from Uganda), is a variety of Cape aloes produced by careful evaporation. Aloe Purificata, U.S.P., is prepared by adding alcohol to melted aloes, stirring thoroughly, straining, and evaporating the strained liquid; the product occurs in irregular, brittle, dull-brown or reddish-brown pieces, and is almost entirely soluble in alcohol (95 per cent.).
CURAÇAO ALOES is obtained from A. chinensis, Baker. It was formerly produced on the island of Barbados, and is still frequently, but improperly, called Barbados aloes; it is now almost entirely made on the Dutch islands of Curaçao, Aruba, and Bonaire, by boiling the aloe juice down and pouring the viscid residue into empty spirit cases, in which it is allowed to solidify. Formerly gourds of various sizes were used, but aloes in gourds is now seldom seen. It is usually opaque, or, as it is termed, "livery," and varies in colour from bright yellowish or reddish-brown to black or nearly black, the former variety being the more esteemed. It is not infrequently vitreous; small fragments are then of a deep garnet-red colour and transparent; it is then known as "Capey Barbados" and is less valuable, but may become livery and more valuable by keeping. Curaçao aloes possesses the nauseous and bitter taste that is characteristic of all aloes, and a disagreeable penetrating odour.
Constituents.—The most important constituents are the two aloins, barbaloin and isobarbaloin, which constitute the so-called "crystalline" aloin. The quantity of this present in the drug has been variously estimated at amounts ranging from 10 to more than 30 per cent. Another constituent is amorphous aloin (ß-barbaloin), a substance found in greatest abundance in Cape and Uganda aloes; it can be formed from barbaloin by heating it at a temperature of 160° to 165° for about three hours. The drug contains, in addition to crystalline and amorphous aloin, resin, aloe-emodin and watersoluble substances other than aloin, the proportion in which these are present being also very variable. The resin is a compound of barbaloresinotannol with cinnamic acid; the nature of the watersoluble substances other than aloin is unknown. The drug contains only traces of aloe-emodin (trihydroxy-methyl-anthraquinone), which is also obtainable by the action of alcohol, sodium peroxide, or mineral acids upon barbaloin, an uncrystallisable sugar (aloinose) being another product of the hydrolysis. Curaçao aloes may be best identified by means of the cupraloin reaction. If 10 mils of an aqueous solution of aloes (1 to 1000) be mixed with 1 mil of a 5 per cent. solution of copper sulphate, 1 mil of a saturated solution of sodium chloride, and a few drops of hydrocyanic acid, a fine, deep, persistent claret colour is rapidly developed. This reaction is due to the isobarbaloin contained in the drug, and is yielded by no other commercial aloes. In common with all other aloes, an aqueous solution of Curaçao aloes assumes a fine green fluorescence on the addition of borax. Solutions of Curaçao and other aloes gradually undergo change, and may after a month no longer react normally, at the same time losing their bitterness; this change is ascribed to a gradual hydrolysis of the aloin, and probably of other glucosidal bodies present in the drug. Curaçao aloes should be of a rich, livery, brown colour, and uniform fracture; it should be almost entirely soluble in 60 per cent. alcohol, and contain not more than 30 per cent. of substances insoluble in water, or 12 per cent. of moisture. It should yield not more than 3 per cent. of ash.
SOCOTRINE ALOES is prepared to a certain extent on the island of Socotra, but probably more largely on the African and possibly also on the Arabian mainland, from the leaves of Aloe Perryi, Baker. It is imported usually in kegs in a pasty condition, and subsequent drying is necessary. It may be distinguished from Curaçao aloes by its different odour, and by the negative result of the cupraloin reaction. Much of the dry drug is characterised by the presence of small cavities in the fractured surface, but the variety of Socotrine aloes distinguished as Zanzibar often very closely resembles Curaçao in appearance.
Constituents.—The chief constituents are barbaloin (formerly called socaloin and zanaloin) and β-barbaloin, no isobarbaloin being present in this variety of aloes; resin, water-soluble substances other than aloin, and aloe-emodin are also present, but the proportion in which they are present is not definitely known, though the percentage of aloin is variously stated at from 4 to 10 per cent. The resin probably consists of capaloresinotannol combined with paracumaric acid. No good positive test of identity is known for this variety of aloes, the best being the reddish-brown or yellowish-brown (not crimson colour) which it imparts to nitric acid. Socotrine aloes should be of a dark reddish-brown colour, and almost entirely soluble in alcohol. Not more than 50 per cent. should be insoluble in water, and it should yield not more than 3 per cent. of ash.
CAPE ALOES is prepared in Cape Colony from Aloe ferox, Miller. It is often preferred to other varieties on the Continent, but is chiefly employed in this country for veterinary purposes. Cape aloes almost invariably occurs in the vitreous modification; it forms dark-coloured masses, which break with a clean, glassy fracture, and exhibit in thin splinters a yellowish, reddish-brown, or greenish tinge. Its glassy appearance and very characteristic odour sufficiently distinguish it from other varieties of aloes. Confirmatory evidence may be found in the negative result with the cupraloin test and in the green colouration gradually produced with nitric acid. Uganda aloes is also obtained from Aloe ferox; it occurs in bricks or fragments of hepatic yellowish-brown colour with a bronze-gold fracture, and its odour resembles that of Cape aloes.
Constituents.—It contains 9 per cent. or more of barbaloin (formerly known as capaloin) and β-barbaloin. Only traces of isobarbaloin are present. The resin of Cape aloes consists of capaloresinotannol combined with paracumaric acid. Cape aloes should not contain more than 12 per cent. of water; it should yield at least 45 per cent. of aqueous extract, but not more than 2 per cent. of ash. Uganda aloes yields about 6 per cent. of aloin, part of which is β-barbaloin.
Action and Uses.—Aloes is employed as a purgative. An ordinary small dose takes from fifteen to eighteen hours to produce an effect; this may be due to the fact that aloin itself is inactive but is slowly converted, in the bowel, into an amorphous body which induces the local irritation; its action is therefore delayed, and is exerted mainly on the large intestine. The purgative action is increased by the addition of small quantities of iron, alkaline salts, or soap. Given in small doses, it is one of the most valuable drugs in the treatment of chronic constipation. The pronounced action of aloes on the large intestine induces some pelvic congestion, and it is therefore employed as an emmenagogue in amenorrhoea, generally with iron. Aloes should not be used by plethoric persons nor when there is intestinal irritation or catarrh, or hepatic congestion. Its use is contra-indicated for pregnant or nursing women. Preparations of aloes are rarely prescribed alone; they require the addition of carminatives to moderate the tendency to griping. The compound preparations of aloes in use generally contain such correctives, but powdered aloes and the extracts of aloes represent the crude drug. Aloes in one form or another is the commonest domestic medicine, and is the basis of most proprietary or so-called "patent" pills. There is little to choose medicinally between the Barbados and Socotrine varieties, but the former is somewhat more powerful.
Dose.—1 to 3 decigrams (2 to 5 grains).
- Decoctum Aloes Compositum, B.P.—COMPOUND DECOCTION OF ALOES. Syn.—Baume de Vie.
- Extract of Barbados aloes, in coarse powder, 1; myrrh, in coarse powder, 0.5; saffron, 0.5; potassium carbonate, 0.5; extract of liquorice, 4; compound tincture of cardamoms, 30; distilled water, sufficient to produce 100. This decoction is employed as a purgative, and is especially useful in amenorrhoea, for which it is commonly prescribed with Mistura Ferri Composita; it acts partly by causing pelvic congestion. The preparation loses its bitterness on keeping, owing to the action of the alkali, which forms a soap. Old preparations of aloes specifically excite the uterus after absorption; fresh preparations do not possess this property. Dose.—15 to 60 mils (1/2 to 2 fluid ounces).
- Enema Aloes, B.P., 1885.—ENEMA OF ALOES.
- Aloes, 40 grains; potassium carbonate, 15 grains; mucilage off starch, 10 fluid ounces. This quantity is sufficient for one purgative enema.
- Extractum Aloes, U.S.P.—EXTRACT OF ALOES.
- Aloes (Barbados or Socotrine), 10; boiling water, 100. The aloes is exhausted with boiling water and the solution evaporated to dryness on a water-bath. Average dose.—1 1/4 decigrams (2 grains).
- Extractum Aloes Barbadensis, B.P.—EXTRACT OF BARBADOS ALOES.
- Barbados aloes, broken small, 10; distilled water, boiling, 100. Three parts of the resulting extract is about equal to four parts of the powdered aloes. This extract may be made into a pill with diluted alcohol, preferably with the addition of a little inert vegetable powder. It is a common ingredient of "dinner pills," with mastic, extract of nux vomica, and belladonna or henbane. The addition of a small quantity of soap hastens the action of aloes preparations. Dose.—1/2 to 2 1/2 decigrams (1 to 4 grains).
- Extractum Aloes Socotrinae, B.P., 1885.—EXTRACT OF SOCOTRINE ALOES.
- Socotrine aloes, broken small, 10; distilled water, boiling, 100. One part of the resulting extract is about equal to 2 parts of the powdered aloes. It may be made into a pill with diluted alcohol, preferably with the addition of a little inert vegetable powder. Dose.—1/2 to 2 1/2 decigrams (1 to 4 grains).
- Pilula Aloes Barbadensis, B.P.—PILL OF BARBADOS ALOES.
- Each 4-grain pill contains about 2 grains of Barbados aloes; 1 grain of hard soap, and 1/8 minim of oil of caraway, massed with confection of roses. Dose.—1 or 2 pills.
- Pilula Aloes et Asafetidae, B.P.—PILL OF ALOES AND ASAFETIDA.
- Each 4-grain pill contains about 1 grain each of Socotrine aloes, asafetida, and hard soap, massed with confection of roses. Dose.—1 or 2 pills.
- Pilula Aloes et Ferri, B.P.—PILL OF ALOES AND IRON.
- Each 4-grain pill contains about 1/2 grain of exsiccated ferrous sulphate 1 grain of Barbados aloes, and 1 1/2 grains of compound powder of cinnamon, massed with syrup of glucose. Dose.—1 or 2 pills.
- Pilula Aloes et Myrrhae, B.P.—PILL OF ALOES AND MYRRH.
- Each 4-grain pill contains about 2 grains of Socotrine aloes, and 1 grain of myrrh, massed with syrup of glucose. Dose.—1 or 2 pills.
- Pilula Aloes Socotrinae, B.P.—PILL OF SOCOTRINE ALOES.
- Each 4-grain pill contains about 2 grains of Socotrine aloes, 1 grain of hard soap, and 1/8 minim of oil of nutmeg, massed with confection of roses. Dose.—1 or 2 pills.
- Pilulae Aloes, U.S.P.—PILLS OF ALOES.
- Each pill contains about 2 grains each of purified aloes, U.S.P., and hard soap. Average dose.—2 pills.
- Pilulae Aloes Compositae, B.P.C.—COMPOUND ALOES PILLS. Syn.—Baird's Pills.
- Each pill contains 1 and 1 scammony, 1/4 grains of Barbados aloes; 1/4 grain of ipecacuanha root; 1 1/4 grains of 1/4 grains of green extract of hyoscyamus, massed with syrup of glucose. Dose.—1 or 2 pills.
- Pilulae Aloes Dilutae, B.P.C.—MILD ALOES PILLS. Syn.—Marshall Hall's Pills.
- Each pill contains 1 grain each of Barbados aloes, extract of liquorice, hard soap, and treacle, with a sufficient quantity of distilled water. Dose.—1 or 2 pills.
- Pilulae Aloes et Ferri, U.S.P.—PILLS OF ALOES AND IRON.
- Each pill contains about 1 grain each of purified aloes, U.S.P., exsiccated ferrous sulphate, and aromatic powder, U.S.P., massed with confection of rose, U.S.P. Average dose.—2 pills.
- Pilulae Aloes et Ipecacuanhae, B.P.C.—ALOES AND IPECACUANHA PILLS. Syn.—Chapman's Dinner Pills.
- Each pill contains 1 minim of and 1/4 1/2 grains each of Barbados aloes and mastic, 1 grain of ipecacuanha root, oil of fennel. Dose.—1 or 2 pills.
- Pilulae Aloes et Ipecacuanhae Compositae, B.P.C.—COMPOUND ALOES AND IPECACUANHA PILLS. Syn.—Burney Yeo's Dinner Pills.
- Each pill contains 1 nux of 1/2 grains of extract of Barbados aloes; 1/2 grain each of ipecacuanha root, extract vomica, and hard soap; and 1 grain of quinine sulphate. Dose.—1 pill, immediately before dinner.
- Pilulae Aloes et Mastiche, B.P.C.—ALOES AND MASTIC PILLS. Syn.—Dinner Pills.
- Each pill contains 2 grains of Barbados aloes, and 1 grain of mastic, massed with confection of roses. Dose.—1 or 2 pills.
- NOTE.—Pills produced by slight variants on this formula are known as Lady Webster's Pills, Lady Hesketh's Pills, Thomson's Antibilious Pills, and Crespigny's Pills.
- Pilulae Aloes et Mastiches, U.S.P.—PILLS OF ALOES AND MASTIC.
- Each pill contains about 2 grains of purified aloes, U.S.P., 3/5 grain of mastic, and 1/2 grain of red rose petals, massed with 49 per cent. alcohol. Average dose.—2 pills.
- Pilulae Aloes et Myrrhae, U.S.P.—PILLS OF ALOES AND MYRRH.
- Each pill contains about 2 grains of purified aloes, 1 grain of myrrh, and 3/5 grain of aromatic powder, U.S.P., massed with syrup. Average dose.—2 pills.
- Pilulae Aloes et Nucis Vomicae, B.P.C.—ALOES AND NUX VOMICA PILLS.
- Each pill contains 2 grains of Barbados aloes, 1/4 grain of extract of nux vomica, and 1/6 grain of alcoholic extract of belladonna, massed with alcohol (60 per cent.). Dose.—1 or 2 pills.
- Pilulae Aloes Ipecacuanhae et Rhei, B.P.C.—ALOES, IPECACUANHA, AND RHUBARB PILLS. Syn.—Gregory's Dinner Pills.
- Each pill contains 1 grain each of extract of Barbados aloes, ipecacuanha root, rhubarb root, and hard soap. Dose.—1 or 2 pills.
- Pilulae Rufi, B.P.C.—RUFUS PILLS.
- Each pill contains 2 grains of Socotrine aloes, 1 grain of myrrh, 1/2 grain of dried saffron, massed with treacle and glycerin. Dose.—1 or 2 pills.
- Pulvis Aloes et Canellae, B.P.C.—ALOES AND CANELLA POWDER. Syn.—Hiera Picra.
- Socotrine aloes, 4; canella bark, 1. This powder is employed as a purgative and emmenagogue. to 6 Dose.—2 decigrams (3 to 10 grains).
- Tablettae Aloes et Ferri, B.P.C.—ALOES AND IRON TABLETS.
- Exsiccated ferrous sulphate, 1/2 grain; Barbados aloes, 1 grain; compound powder of cinnamon, 1 grains; in 1/2 each tablet. Approximately equal to 3 decigrams (5 grains) of the corresponding official pill mass. Dose.—1 or 2 tablets.
- Tablettae Aloes et Myrrhae, B.P.C.—ALOES AND MYRRH TABLETS.
- Socotrine aloes, 2 grains; myrrh, 1 grain; in each tablet. Approximately equal to 3 decigrams (5 grains) of the corresponding official pill mass. Dose.—1 or 2 tablets.
- Tablettae Aloes et Nucis Vomicae et Belladonnae, B.P.C.—ALOES, NUX VOMICA AND BELLADONNA TABLETS.
- Barbados aloes, 2 grains; extract of nux vomica, 1/4 grain; alcoholic extract of belladonna, 1/6 grain, in each tablet. Given for chronic constipation. Dose.—1 or 2 tablets.
- Tinctura Aloes, B.P.—TINCTURE OF ALOES.
- Extract of Barbados aloes, 2.5; liquid extract of liquorice, 15; alcohol (45 per cent.), sufficient to produce 100. Dose.—2 to 4 mils (1/2 to 1 fluid drachm), for repeated administration; for a single dose, 6 to 8 mils (1 1/2 to 2 fluid drachms).
- Tinctura Aloes, U.S.P.—TINCTURE OF ALOES, U.S.P.
- Purified aloes, in No. 40 powder, 10; liquorice root, in No. 40 powder, 20; alcohol (49 per cent.), a sufficient quantity to produce 100. Average dose.—2 mils (30 minims).
- Tinctura Aloes Composita, Ph.G. and B.P.C.—COMPOUND TINCTURE OF ALOES. Syn.—Elixir ad Longam Vitam.
- Barbados aloes, 3; gentian root, 0.5; rhubarb root, 0.5; zedoary root, 0.5; saffron, 0.5; alcohol (70 per cent.), by weight, 100. Used as a bitter and purgative in atonic dyspepsia with constipation. Dose.—4 to 8 mils (1 to 2 fluid drachms).
- Tinctura Aloes et Myrrhae, B.P.C.—TINCTURE OF ALOES AND MYRRH. Syn.—Elixir Proprietatis.
- Socotrine aloes, 10; saffron, 5; tincture of myrrh, 100. Used as a purgative and emmenagogue. Dose.—4 to 8 mils (1 to 2 fluid drachms).
- Tinctura Aloes et Myrrhae, U.S.P.—TINCTURE OF ALOES AND MYRRH, U.S.P.
- Purified aloes, U. S. P., in No. 40 Powder, 10; myrrh, in No. 40 powder, 10; liquorice root, in No. 40 powder, 10; alcohol (71 per cent.), sufficient to produce 100. Average dose.—2 mils (30 minims)
- Tinctura Antiperiodica, B.P.C.—ANTIPERIODIC TINCTURE. Syn.—Warburg's Tincture.
- Socotrine aloes, 2.75 rhubarb root, 0.91; angelica fruit, 0.91; elecampane root, 0.46; saffron, 0.46; fennel fruit, 0.46; prepared chalk, 0.46; gentian root, 0.23; zedoary root, 0.23; cubebs, 0.23; myrrh, 0.23; white agaric, 0.23; opium, 0.03; black pepper, 0.05; cinnamon bark, 0.09; ginger, 0.09; quinine sulphate, 2; camphor, 0.23; alcohol (60 per cent.), to 100. Said to be of great value in ague and malarial fevers. It is sometimes ordered without aloes (Tinctura Antiperiodica sine Aloe). In acute cases the full dose is given and repeated in three hours, food being abstained from between the two doses, except for brandy or beef tea if required. Dose.—4 to 15 mils (1 to 4 fluid drachms).
- Vinum Aloes, B.P., 1885.—ALOES WINE. Syn.—Wine of Aloes.
- Socotrine aloes, crushed, 3.75; cardamom seeds, bruised, 0.5; ginger, in coarse powder, 0.5; sherry, sufficient to produce 100. Aloes wine is used as a stomachic bitter and laxative. Dose.—4 to 8 mils (1 to 2 fluid drachms).
The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.