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and its official description corresponds with the granulated sugar of comThe permanency of these preparations chiefly depends on their possessing the proper relative proportions of sugar and water. They are prepared either by solution with heat, by agitation without heat, by adding a medicated liquid to simple syrup, by digestion or maceration, or by cold percolation; these processes being all officially directed except the last. They are best preserved by being poured while hot into pint bottles, which should be corked securely while full, and the tops dipped into melted sealing-wax. Fermented syrups are useless for dispensing purThe number of official syrups is 34, as follows, viz. :·
Syrupus Rubi Idæi.
Syrupus Sarsaparillæ Compositus.
Syrupus Scillæ Compositus.
Mellita, Honeys,-differ from syrups merely in their being prepared with honey as a base. The Oxymel and Oxymel Scilla of the B. P. are similar preparations, containing also Acetic Acid. There are 3 official Honeys, including two forms of honey itself, viz. :
Mucilagines, Mucilages,—are thick, viscid liquids prepared by dissolving gum in water, or by extracting with water the mucilaginous principles from certain plants. They are easily spoiled and should be kept only in small quantities. The official Mucilages number 5, as follows, the three first-named being prepared without heat, the two last-named with heat, viz.:—
Mucilago Sassafras Medullæ.
Misturæ, Mixtures,-in official pharmacy are aqueous preparations of insoluble substances held in suspension by a suitable vehicle. In extemporaneous pharmacy the term mixture has a wider signification, as explained under that head. They are generally prepared extemporaneously upon prescriptions, as few of them are of the stability necessary to insure
their preservation beyond a few days. The official Mixtures number 11, of which one (Mistura Ferri et Ammonii Acetatis) is misnamed, and should be entitled a Solution, as it does not contain any insoluble subTheir names are as follows, viz. :—
Mistura Ferri Composita.
Mistura Ferri et Ammonii Acetatis.
Mistura Potassii Citratis.
Of the above-named, the first two are simple gum-resin emulsions, the third is a seed-emulsion, the fourth an egg-emulsion; the next four contain insoluble powders in suspension by the aid of gum arabic, sugar, etc., the next two do not contain insoluble powders in suspension, while the last is an effervescing mixture.
Infusa, Infusions, are prepared by treating vegetable substances with hot or cold water without boiling. Cold water is preferred when the drug contains a desirable volatile principle, or when its active ingredient is injured by heat. The drug should be coarsely comminuted, sliced or bruised, and treated by maceration or percolation with the proper quantity of water, which in the absence of specific directions to the contrary should be 10 parts by weight to 1 of the drug. These preparations should be freshly made when required, as they are very prone to decomposition. The number of official Infusions is 5, viz. :—
Infusum Pruni Virginianæ.
The proportions of drug to menstruum in the official infusions vary from 11⁄2 per cent. in the case of Digitalis to 4 per cent. in the case of Wild Cherry and 6 per cent. in the case of the others. Alcohol is an ingredient of the Infusion of Digitalis to prevent decomposition.
Many dispensing pharmaceutists are in the habit of making infusions from concentrated alcoholic tinctures or from fluid extracts. It is a very reprehensible practice, especially in those cases where the active ingredients are of a resinous nature and therefore precipitated when the alcoholic solution is added to water.
Decocta, Decoctions,-are made by boiling vegetable substances with water. As very few drugs contain active ingredients which are not injured by heat, these preparations have never obtained favor with scientific physicians. There are only 2 official Decoctions, viz. :
Decoctum Sarsaparillæ Compositum.
The general official formula prescribes that an ordinary decoction, the strength of which is not directed by the physician, nor specified by the Pharmacopoeia, shall be prepared in the proportion of 1 part of the substance to 9 of water. Decoctum Cetrariæ is one-half the aforesaid strength, while the Compound Decoction of Sarsaparilla is of the full strength as to its chief ingredient.
Extracta Fluida, Fluid Extracts,- —are permanent concentrated solutions of vegetable drugs, of uniformly definite strength if the crude drugs are so, a cubic centimeter (m 16.23) in each case representing the medicinal powers of one gramme (gr. 15.43) of the drug, or approximately a minim of the finished preparation representing the active constituents of a grain of the drug. They are officially directed to be prepared by percolation and partial evaporation, the menstrua employed being usually Alcohol, diluted Alcohol, or Alcohol and Water in various proportions, though a few are percolated with water, the alcohol being afterwards added. In several instances Glycerin in different proportions is added to the first menstruum, and in the menstruum used for the extraction of Aconite root Tartaric Acid is an ingredient. In the preparation of the fluid extract of Prunus Virginiana, the extraction is preceded by maceration with water and glycerin, in order to permit of the formation of Hydrocyanic Acid by the reaction of the amygdalin and emulsin of the bark upon each other, which takes place only in the presence of water. The glycerin aids to keep the dissolved matters in perfect solution, and also to better retain the acid and volatile oil formed during the process. The fluid extract of Glycyrrhiza is prepared with a first menstruum containing Ammonia, and that of Lactucarium is first treated with Ether and then put through an elaborate process in order to obtain a preparation which will make a clear mixture with water, syrup or glycerin. The menstruum directed to be used in each case is intended to be that which will thoroughly extract all the active constituents of the drug and at the same time will leave the inert soluble matters behind in the rejected portion, known as the marc. In manufacturing fluid extracts on a large scale, modifications of the official processes are necessary, and the methods used are generally percolation and maceration with hydraulic pressure, vacuum maceration followed by percolation, percolation with incomplete exhaustion, or repercolation. The number of official Fluid Extracts is 79. They are named in the following list, the letters following each one in parentheses showing the character of its menstruum, and representing Alcohol, Diluted Alcohol, Alcohol and Water, or Glycerin, by their respective initials.
Extractum Aconiti Fluidum (A).
Ext. Aurantii Amari Fl. (A,W1).
Ext. Brayeræ Fl. (A).
Ext. Buchu Fl. (A,W1).
Ext. Lactucarii Fl. (A,W1).
Ext. Rhois Glabræ Fl. (DA,G1).
Ext. Scutellar æ Fl. (A,W2).
In nine instances only does the Pharmacopoeia direct the making of other preparations from corresponding fluid extracts, these nine being the Syrups of Krameria, Lactucarium, Rubus, Senega, and Ginger, the Extract of Ergot, the Liniment of Belladonna, the Ointment of Mezereum, and the mixture of Rhubarb and Soda. Notwithstanding this fact it is a common practice for dispensing pharmaceutists to make tinctures, syrups, infusions, etc., from fluid extracts; and some manufacturers put a label on the bottles containing their fluid extracts, giving the formulæ for so preparing other preparations. This practice is illegitimate, and tends to still further degrade the profession of pharmacy into a mere trade, so far as all dispensing is concerned.
A large number of unofficial fluid extracts are manufactured and for sale, one house alone carrying over 400 such on their catalogue. Normal Liquids are a class of superior fluid extracts introduced by Parke, Davis & Co., which are claimed to be adjusted to a maximum strength by accurate assays for alkaloidal strength made at each stage of their manipulation, irrespective of the amount of material required, which in the case of official fluid extracts is prescribed by the Pharmacopoeia, regardless of the varying quality of drugs in the market. This firm prepares Normal Liquids of Aconite, Veratrum Viride, Belladonna (root or leaves), Cannabis Indica, Cinchona Calisaya, Cinchona Rubra, Colchicum
(root or seed), Conium, Ergot, Digitalis, Gelsemium, Hyoscyamus, Ipecacuanha, Podophyllum, Nux Vomica, Rhubarb, and Stramonium (seed or leaves). Of these preparations one cubic centimeter is equivalent to one gramme of the corresponding drug of standard alkaloidal strength. A fluid extract of Belladonna leaves may contain .25 or .45 per cent. of atropine, according to the quality of the drug employed; a Normal Liquid will contain invariably .4 per cent. of the alkaloid, so that in a given dose it may be relied upon to produce a certain effect.
Tincturæ, Tinctures,-are alcoholic solutions of medicinal substances; and with one official exception (Tincture of Iodine), are made from nonvolatile bodies. They are prepared by percolation, maceration, solution or dilution; the menstrua employed being chiefly Alcohol, and diluted Alcohol of various strengths, though in a few cases the Aromatic Spirit of Ammonia, and mixtures of Alcohol, Water and Glycerin are directed to be used. The Pharmacopoeia prescribes a general formula for Tinctures of Fresh Herbs, according to which, when not otherwise directed, these preparations are to be made by macerating 50 parts of the Fresh Herb, bruised or crushed, with 100 parts of Alcohol for 14 days, then expressing the liquid and filtering. Of the 72 official Tinctures 2 are made with 5 per cent. of the ingredient, 20 with 10 per cent., 9 with 15 per cent., 23 with 20 per cent., I with 35 per cent., 1 (Aconite) with 40 per cent., 3 with 50 per cent., and 1 (Soap) with 65 per cent.; the others varying in strength from 0.4 per cent. in the case of Paregoric to 26 per cent. in that of the Compound Tincture of Benzoin. Fifty-four are made by percolation, a few by solution or dilution, and the rest by maceration. The offi cial Tinctures are as follows, the figures placed after each giving the number of grains of the active ingredients in each fluid-drachm, viz.:—