Aloinum, B.P., Aloin.

Related entry: Aloe

Aloin is a crystalline substance extracted from aloes, and is obtained chiefly from Curaçao aloes, but may be obtained from other kinds of aloes. It is also official in the U.S.P. It occurs as yellow, acicular crystals or crystalline powder, without odour, but with the taste of aloes. Aloin is rapidly decomposed in alkaline solutions, but not in neutral or acid solutions.

Slightly soluble in water, more soluble in alcohol or acetone almost insoluble in ether.

Constituents.—Aloin obtained from Curaçao, or from true Barbados, aloes consists of barbaloin, C₂₁H₂₀O₉, and isobarbaloin, both crystalline substances, in approximately equal proportions. Barbaloin is a methyl-anthraquinone derivative of glucosidal character, yielding aloe-emodin (trihydroxy-methyl-anthraquinone) and aloinose by hydrolysis; it is converted into amorphous β-barbaloin by heating it at a temperature of 160° to 165° for about three hours. Isobarbaloin is distinguished by yielding the cupraloin reaction. Aloin obtained from Socotrine or Zanzibar aloes consists chiefly of barbaloin, but also contains β-barbaloin; isobarbaloin is absent.

Action and Uses.—Aloin acts in the same way as aloes; it has the disadvantage of being more easily absorbed than aloes, and has sometimes produced signs of renal irritation during excretion in the urine. It may be administered in the form of cachets, pills, or tablets, and is frequently combined with extract of nux vomica or strychnine, ferrous sulphate, myrrh, ipecacuanha, and extract of belladonna. It is sometimes added to glycerin suppositories (½ to 1 grain in each).

Dose.—3 to 12 centigrams (½ to 2 grains).

PREPARATIONS.

Pilulae Aloini Compositae, B.P.C.—COMPOUND ALOIN PILLS. Syn.—Sir Andrew Clark's Liver Pills.

Aloin, ½ grain; extract of nux vomica, ½ grain; ferrous sulphate, ½ grain; myrrh, ½ grain; hard soap, ½ grain, in each pill. Dose.—1 pill.
NOTE.—These pills are sometimes ordered with the addition of ½ grain each of ipecacuanha and extract of belladonna to each pill.

Pilulae Aloini et Podophylli Compositae, B.P.C.—COMPOUND ALOIN AND PODOPHYLLUM PILLS.

Aloin, 1/10 grain; oleoresin of capsicum, 1/20 grain; jalap resin, 1/10 grain; podophyllum resin, 3/20 grain; extract of nux vomica, 1/20 grain; green extract of hyoscyamus, 1/20 grain, in each pill. Dose.—1 to 4 pills.
NOTE.—These pills have approximately the same composition as many of the so-called "Little Liver Pills.''

Pilulae Aloini et Strychninae Compositae, B.P.C.—COMPOUND ALOIN AND STRYCHNINE PILLS.

Aloin, ⅕ grain; strychnine, 1/50 grain; green extract of belladonna, 1/10 grain; ipecacuanha root, 1/20 grain, in each pill, with milk sugar and syrup of glucose. Dose.—1 or 2 pills.

Pilulae Laxativae Compositae, U.S.P.—COMPOUND LAXATIVE PILLS.

Aloin, 13 decigrams; strychnine, 5 centigrams; ipecacuanha, in fine powder, 4 decigrams; liquorice, in fine powder, 46 decigrams; extract of belladonna leaves, 8 decigrams; with a sufficient quantity of syrup to form a mass which is to be divided into 100 pills. Average dose.—2 pills.

Tablettae Aloini Compositae, B.P.C.—COMPOUND ALOIN TABLETS.

Aloin, ½ grain; ipecacuanha, ¼ grain; extract of mix vomica, ⅛ grain; in each tablet. Weaker compound tablets of aloin, containing 1/10 or ⅕ grain, may also be prepared. Dose.—1 or 2 tablets.

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