Cinchonae Rubrae Cortex, B.P., Red Cinchona Bark.

Red cinchona bark (Peruvian bark) is obtained from the stem and branches of cultivated plants of Cinchona succirubra, Pavon (N.O. Rubiaceae), a native of South America, but cultivated in British India, Java, Ceylon, and elsewhere. It is imported chiefly from Java. Cinchona, U.S.P., is the dried bark of C. Ledgeriana, C. Calisaya, or C. officinalis, that of C. succirubra being distinguished as red cinchona. The drug occurs in quills or more or less incurved pieces of varying size, often about 35 millimetres in diameter, the bark itself being from 2 ½ to 6 millimetres in thickness. The outer surface is dull brownish-grey or reddish-brown in colour, often grey with lichens, and more or less strongly wrinkled longitudinally, older pieces also bearing reddish warts; small transverse cracks are sometimes seen. The characteristic red-brown inner surface shows on scraping a yellowish-brown interior, which darkens on exposure. The bark is spongy in texture, and has no perceptible odour, but a distinctly bitter and astringent taste. It should not yield more than 5 per cent. of ash on incineration. Other quilled barks appearing in commerce are those of C. Calisaya, C. officinalis, C. lancifolia, and C. Ledgeriana. Calisaya bark or yellow cinchona occurs in firm hard quills, the periderm of which is liable to exfoliate, and bears well-marked longitudinal and transverse cracks. It contains about 6 per cent. of alkaloids, of which about one-half is quinine. Pale cinchona or crown bark, from C. officinalis, is also firm, the quills being small and rough to the touch. Longitudinal cracks and numerous small transverse cracks with recurved edges mark the outer surface. It contains about 5 per cent. of alkaloids, of which about three-quarters is quinine. Colombian bark, from C. lancifolia, is a soft bark, with a more or less smooth surface marked with patches of silvery-grey cork. It contains about 2 per cent. of alkaloids, of which very little is quinine. Ledger bark closely resembles calisaya, but is marked with more numerous and less conspicuous long fissures and transverse cracks. It yields from 6 to 7 per cent. of total alkaloids, and from 3 to 5 per cent. of quinine.

Constituents.—The bark should yield between 5 and 6 per cent. of total alkaloids, of which not less than half should consist of quinine and cinchonidine. Other constituents are cinchonine, quinidine, hydrocinchonidine, quinamine, homocinchonidine, hydroquinine, quinic, and cinchotannic acids, a bitter amorphous glucoside, starch, and calcium oxalate.

Action and Uses.—Cinchona bark is a bitter tonic and stomachic. It has the action of quinine, but is also astringent, more irritating to the stomach and intestines, and is more slowly absorbed. The liquid extract is used as a tonic for convalescents, with hydrobromic acid and tincture of nux vomica, and is employed as a dipsomania "cure." The powdered bark is not much used internally, except as a domestic bitter wine, made by macerating the bark in port wine and decanting. It is a frequent and useful ingredient of astringent tooth powders. Liquid preparations of cinchona are best administered in an acid medium, which will keep the alkaloids in solution. Decoction of cinchona and the tinctures are, however, frequently prescribed with ammonium carbonate, which precipitates the alkaloids, so that they sometimes need suspending with syrup or mucilage of gum acacia. Cinchona is a useful astringent for the throat, and the decoction or acid infusion is used in gargles.

Dose.—¼ to 4 grammes (5 to 60 grains).

PREPARATIONS.

Decoctum Cinchonae, B.P., 1885.—DECOCTION OF CINCHONA.

Red cinchona bark, in No. 20 powder, 6.25; distilled water, sufficient to produce 100. Add the powdered bark to 100 of the water, boil for ten minutes, strain when cold to avoid subsequent deposition of cinchotannic acid, which is soluble in hot water, and make up to the required volume, if necessary, by passing distilled water through the strainer. Decoction of cinchona is a suitable vehicle for alkaline bitter tonics, and, on account of its astringency, is a useful addition to gargles. Dose.—15 to 60 mils (½ to 2 fluid ounces).

Elixir Cinchonae, B.P.C.—ELIXIR OF CINCHONA. Syn.—Elixir Calisayae; Elixir of Calisaya.

Tincture of yellow cinchona, 15; with syrup, glycerin, and aromatic elixir to 100. Elixir of cinchona is a pleasant bitter tonic. Dose.—2 to 4 mils (½ to 1 fluid drachm).

Extractum Cinchonae Liquidum, B.P.—LIQUID EXTRACT OF CINCHONA. Syn.—Liquor Cinchonae.

Red cinchona bark, in No. 60 powder, 128; hydrochloric acid, 4; glycerin, 16; alcohol, a sufficient quantity; distilled water, a sufficient quantity. Add the hydrochloric acid and glycerin to 640 of the water, mix the drug with the resulting liquid, and allow it to macerate for forty-eight hours with frequent agitation; then transfer the mixture to a percolator and continue the percolation with water until the percolate measures 1920, or ceases to give a precipitate when an excess of solution of potassium hydroxide is added. Place the resulting percolate in a porcelain or enamelled iron vessel, and reduce by evaporation to 128, at a temperature not exceeding 82°; then standardise as officially directed, adjusting the strength of the extract so that the finished product shall contain 5 per cent. of alkaloids and 12.5 per cent. of alcohol. Liquid extract of cinchona is used as a bitter or mild astringent. It is incompatible with alkalies, alkali carbonates (slight effervescence), iodides and salicylates, though they are frequently prescribed together. In dispensing such mixtures the liquid extract should be mixed with any syrup or glycerin ordered, and poured into some of the aqueous vehicle containing a little mucilage, the salts being subsequently added in as dilute a solution as possible. If the liquid extract be poured into a solution of the salts, a lumpy and unsightly mixture will result. The extract should preferably be prescribed with an acid medium; with diluted phosphoric acid and syrup of lemon it forms a pleasant and presentable mixture. Dose.—3 to 10. decimils (0.3 to 1.0 milliliters) (5 to 15 minims).

Fluidextractum Cinchonae, U.S.P.—FLUIDEXTRACT OF CINCHONA.

Cinchona, in No. 60 powder, 100; glycerin, 10; a mixture of alcohol (95 per cent.), 8, and distilled water, 1, a sufficient quantity. This fluidextract is prepared by exhausting the cinchona with the alcohol, glycerin and water, and should contain 4 per cent. w/v of anhydrous ether-soluble alkaloids from cinchona. Average dose.—1 mil (15 minims).

Glycerinum Cinchonae, B.P.C.—GLYCERIN OF CINCHONA. 1 (liquid extract) in 5.

A palatable preparation of cinchona for use in a concentrated form. It is of the same strength as Tinctura Cinchonae, containing 1 per cent. of total alkaloids. Dose.—2 to 4 mils (½ to 1 fluid drachm).

Infusum Cinchonae Acidum, B.P.—ACID INFUSION OF CINCHONA.

Red cinchona bark, in No. 40 powder, 5; aromatic sulphuric acid, 1.25; distilled water, boiling, 100. Pour the water on the powdered bark, mix, add the acid, infuse for an hour in a covered vessel, and strain. This infusion is a bitter tonic. It is incompatible with alkalies, alkali carbonates, soluble benzoates, and salicylates. The infusion is sometimes used in astringent gargles. Dose.—15 to 30 mils (½ to 1 fluid ounce).

Mistura Cinchonae Acida, B.P.C.—ACID CINCHONA MIXTURE.

Each fluid ounce contains 10 minims each of liquid extract of cinchona and diluted nitric acid, and 30 minims of aromatic syrup. This mixture is used as a simple bitter and as a tonic in general debility and during convalescence from acute diseases. Dose.—15 to 30 mils (½ to 1 fluid ounce).

Tinctura Cinchonae, B.P.—TINCTURE OF CINCHONA.

Red cinchona bark, in No. 40 powder, 20; alcohol (70 per cent.), a sufficient quantity. Add 20 of the alcohol to the drug, and allow to macerate for twenty-four hours, then transfer to a percolator; percolate with more of the alcohol until the product measures 70; press the marc, mix the liquids, and filter after allowing to stand for twenty-four hours. Standardise the preparation, as officially directed in the case of Extractum Cinchonae Liquidum, adjusting the strength of the tincture so that the finished product shall contain 1 per cent. w/v of alkaloids. Mixtures containing tincture of cinchona with alkali carbonates, iodides, or salicylates require the addition of one-sixteenth of their bulk of mucilage of tragacanth to suspend the precipitated alkaloidal salts in a diffusible form. The tincture should be added to the mucilage diluted with three or four times its bulk of water, and the salts subsequently added in dilute solution. It is employed chiefly as a bitter. Dose.—2 to 4 mils (½ to 1 fluid drachm).

Tinctura Cinchonae, U.S.P.—TINCTURE OF CINCHONA, U.S.P.

Cinchona, 20; glycerin, 7.5; alcohol (70 per cent.), sufficient to produce 100. The product should contain 0.75 per cent. w/v of anhydrous ether-soluble alkaloids. Average dose.—4 mils (1 fluid drachm).

Tinctura Cinchonae Composita, B.P.—COMPOUND TINCTURE OF CINCHONA.

Dried bitter-orange peel, well bruised, 5; serpentary rhizome, in No. 40 powder, 2.5; cochineal, in powder, 0.32; saffron, 0.63; tincture of cinchona, 50; alcohol (70 per cent.), sufficient to produce 100. Macerate the orange peel, serpentary, cochineal, and saffron with 50 of the alcohol for seven days, with frequent agitation; then strain, press, mix the liquids, add the tincture of cinchona, with sufficient alcohol to make up to the required volume, and filter, after allowing to stand for twenty-four hours. The product should contain from 0.45 to 0.55 per cent. w/v of alkaloids. The recommendations for dispensing Tinctura Cinchonae apply also to this tincture. It is more pleasantly aromatic than the simple tincture. Dose.—2 to 4 mils (½ to 1 fluid drachm).

Tinctura Cinchonae Composita, U.S.P.—COMPOUND TINCTURE OF CINCHONA, U. S. P.

Red cinchona, 10.; dried bitter orange peel, 8; serpentary rhizome, 2; glycerin, 7.5; alcohol (70 per cent.) sufficient to produce 100. Average dose.—4 mils (1 fluid drachm).

Tinctura Cinchonae Flavae, B.P., 1867.—TINCTURE OF YELLOW CINCHONA.

Yellow cinchona bark, in No. 40 powder, 20; alcohol (70 per cent.), a sufficient quantity. The recommendations for dispensing Tinctura Cinchonae apply also to this tincture. Dose.—2 to 8 mils (½ to 2 fluid drachms).

Vinum Cinchonae, B.P.C.—CINCHONA WINE. 1 (of elixir) in 8.

Cinchona wine is used as a bitter. Dose.—15 to 30 mils (½ to 1 fluid ounce).

Vinum Cinchonae Ferratum, B.P.C.—FERRATED CINCHONA WINE.

Iron and ammonium citrate, 0.5; cinchona wine, 100. Ferrated cinchona wine is a chalybeate, and is used as a bitter tonic. Dose.—15 to 30 mils (½ to 1 fluid ounce).

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