« PreviousContinue »
process of mixing. This process will answer for all inorganic substances in powder, except Magnesia, which is best mixed by being thrown on the surface of the water, and after it has sunk to the bottom as a uniform sediment the other ingredients may be added, and the whole well shaken. Froth upon the surface of the liquid, which often arises after agitation, and may prevent the corking of the bottle, will quickly subside on the addition of a few drops of alcohol.
The following are samples of prescriptions for medicines to be administered in mixture form :
Bismuth Mixture for Children. 1 Quinine Mixture for Children. R. Bismuthi Subcarbonatis, . 3ij.
R. Quinina Sulphatis (pulv.), 3ss. Syrupi Acaciæ,
Pulveris Acaciæ, . . 355. Aquæ Cinnamomi, kā, zij. Syrupi Zingiberis, . . Živ. Misce. Signa,-A teaspoonful Fiat mistura. Signa,-A teaspoonevery hour in choleraic diarrhea. | ful thrice daily.
Emulsions (Emulsiones),-are mixtures containing an oil or a resinous substance in a state of minute subdivision, and suspended in water by the aid of some viscid excipient, as gum, soap, alkali, or yolk of egg.
NATURAL EMULSIONS comprise two classes of substances,-(1) those emulsions which exist ready formed in nature, as milk, yolk of egg, the milky juices of plants, etc.; and (2) the mixtures formed by rubbing up gum-resins (as Ammoniacum, Myrrh, Asafetida) with water. Each of the latter substances contains, together with its resin, enough gum to make a perfect emulsion when triturated with water. The manufactured emulsions are simply imitations of the natural ones, sufficient gum being added in case of a resinous substance to cause its suspension in the aqueous diluent.
Emulsification consists in the division of the oily or resinous substance into very minute globules, and surrounding each globule with a thin envelope of the excipient. If properly done the globules will remain mechanically suspended in the water, without any tendency towards recombination. Milk is the best illustration of a natural emulsion, its butter existing in the aqueous portion as very minute globules, each surrounded by a thin film of casein. Yolk of Egg is a dense emulsion, consisting of oil suspended in water by means of albumen.
The EXCIPIENTS which may be used for emulsification are the following, arranged in the order of their most frequent employment, viz. :
Mucilage of Acacia,-used for oils and resins. Powdered Acacia is even better, being made into a mucilage by the process of emulsification; such a mucilage having the advantage of being perfectly fresh when incorporated
with the other ingredients. To give uniformly good results the following proportions in parts by weight should be used, viz. :
Gum Acacia. Water,
I “ “ Oil of Turpentine, " Mucilage of Tragacanth, --may also be used for oils and resins, but it has not proved so satisfactory as the preceding. The same may be said of powdered Tragacanth.
Vitellus, Yolk of Egg,-is an excellent agent for emulsifying oils, but mixtures made with it must be used within a few days, as they will not keep long. One yolk will emulsionize an ounce of fixed oil, and is about equal to half an ounce of Acacia. It is best suited to emulsions of cod-liver oil intended for immediate administration. The official Mistura Chloroformi is an emulsion made with yolk of egg. Glyceritum Vitelli or Glyconin is an official prepa. ration consisting of glycerin and yolk of egg. (See ante, page 392.) One ounce of it will emulsify three ounces of fixed oil.
Liquor Potassa,-may be used for oils, the resulting compound being however a soap rather than an emulsion. Copaiba is usually emulsified by using both a gum and an alkali; a similar process being employed for many of the fixed oils,
Tincture of Senega,-will emulsify fats and oils very efficiently, and even in very small quantities, mx emulsifying an ounce of fixed oil.
Tincture of Quillaia (Soap-bark),-is a good emulsifier for oils, and is much used in Europe for this purpose.
Milk,--is used to emulsify Scammony in the Mistura Scammonii, which is official in the British Pharmacopoeia.
Syrups, Confections and Extracts,—may be used in making emulsions, but are rarely so employed.
Soap,-is occasionally used for emulsifying Oil of Turpentine.
The METHOD of preparing an emulsion which experience has shown to be the best, is as follows:-Add the oil, resin, etc., to a proper quantity of the excipient, and mix both thoroughly in a wedgwood mortar. Then add enough water to equal one-half the weight of the previous mixture, and triturate the whole rapidly and unceasingly until the emulsion is homogeneous and of a whitish color. Next, add the remainder of the water slowly, with continual stirring; finally incorporating the other ingredients, if any.
Emulsions are sometimes flavored and at the same time colored, with such a preparation as the Compound Tincture of Cardamom ; but they present a better appearance when perfectly white. Alcoholic preparations should not be added in large quantity to emulsions made with Acacia or Yolk of Egg, as alcohol will precipitate the emulsifying agent. Volatile Oils require admixture with a fixed oil before being made into an emulsion. Soluble salts should never be prescribed with eniulsions of oils. Acids are incompatible with mixtures which have been emulsified by an alkali. Mucilage used for emulsions should always be freshly prepared.
The following examples of prescriptions for emulsions will represent those generally met with:Cod-liver Oil Emulsion.
Alkaline Emulsion of Copaiba. R. Olei Morrhuæ, . 3ij. R. Copaibæ, Vini, Albi, . .
Liq. Potassæ, . . äå 3ij. Ac. Phos. Dil., . .
Misce, et addeSyrupi, . .
Pulv, Acaciæ, Vitellum, . .
Pulv. Sacchari, . . äā zij. Aq. Amygd. Amar. ad . Zviij. Aq. Menth. Viridis, ad . Misce, et fiat emulsio.
Misce, et fiat emulsio. Sig.–Tablespoonful doses.
Elixirs (Elixiria), -are mixtures containing alcohol, water and sugar, with certain medicinally active ingredients, and supposed to be so prepared as to be particularly palatable, which is seldom true. There is one official elixir, Elixir Aurantii (see ante, page 91), which may be used as a basis for the extemporaneous prescribing of these preparations. The manufacturers have put on the market a great variety of elixirs, and most druggists keep a stock of them on hand prepared in the shop; but they may be ordered by prescription just as any other mixture would be. The substances generally used in this form are as follows:Arsenic.
Iron, Tincture of the Chloride.
Valerianate of Ammonium. Many of these agents are combined with each other, as in the Elixir of Bismuth and Strychnine; Elixir of Calisaya, Iron and Strychnine; Elixir of Gentian with Tincture of Chloride of Iron; Elixir of Iron, Quinine and Strychnine, etc., etc.
A Draught (Haustus),- is an extemporaneous mixture consisting of a single dose, and usually ordered in a vial containing from one to two fuidounces.
Effervescing Draught is one of the best known. It is prepared by neu. tralizing a watery solution of Potassium Bicarbonate with Lemon-juice or Citric Acid, and may be drank during effervescence. When the Co, has escaped it is a solution of Potassium Citrate in water, and corresponds to the official Mistura Potassii Citratis, or Neutral Mixture. (See ante, page 310.)
Black Draught is another well-known preparation of this class. It is official as Infusum Senna Compositum. (See ante, page 354.)
A Drink (Potus),-is a solution or a mixture intended to be used ad libitum, and generally consists of a Potassium or Sodium salt, or a mineral acid, in dilute solution, sweetened and flavored.
The“ Imperial Drink" is made after the following formula: R. Potassii Bitartratis, zij; Olei Limonis, Mv; Aquæ Bullientis, q. s. ad 3xx. M. Fiat pctus. Sig:-Use as a drink.
A Gargle (Gargarysma),-is a mixture or solution for application to the pharynx or to the mouth (mouth-wash). It should never contain any active drug, which would produce dangerous symptoms if swallowed ; nor any agent which would injure the teeth or the mucous membrane. Gargles are ordered and compounded in the same manner as mixtures. They usually contain astringent or disinfecting salts (Alum, Borax, Sulphate of Zinc, Chlorate of Potassium), with a vegetable astringent, and often Honey. The following formulæ will illustrate prescriptions of this class. R. Tr. Guaiaci Ammoniatæ, | R. Acidi Tannici,. . . Tr. Cinchonæ Comp., āă zij.
Potassii Chloratis, · · 3!. Mellis Despumat., : 3V).
Glycerini, · · · 3)... Bene simul agita, et adde
Aquæ, , Potassii Chloratis, . gr. lxxx. | Misce. Sig.–Gargle, to be used Aquæ, q. s. ad . . ziv, every two hours. Fiat gargarysma, Sig.-Gargle.
A Lotion (Lotio) or Wash,-is a solution or mixture of medicinal agents, intended for external application; and usually consists of some soluble, astringent salt, dissolved in water, with perhaps some glycerin or alcohol. A Fomentation (Fotus) is a similar preparation used hot. A Collyrium is an eye-wash, and generally contains a soluble astringent salt dissolved in rose-water or distilled water, in the proportion of gr. j-iv to the 3. The only official preparation suitable for a lotion is the Liquor Plumbi Subacetatis Dilutus, or Lead water. A well-known anodyne, refrigerant and astringent lotion is that represented by the first two of the following prescriptions.
Lead-water and Laudanum. I Lead and Opium Wash. R. Liq. Plumbi Subacetatis, gj | R. Liq. Plumbi Subacrtatis, Tinct. Opii, · · · 3).
Tinct. Opii, · · ãā 3). Aquæ, q. s, ad. . . viij. Aquæ, q. s. ad . . Žviij. M. Fiat lolio. Sig.–Lotion. | M. Fiat lotio. Sig.-Lotion. Gross.
Collyrium of Four Sulphates.
Cupri Sulphatis, Aquæ Destil., . . äā zss. Aluminis,
ää gr. j. M. Fiat collyrium. Sig.-Eye Aquæ Destillatæ, . . 3j. water; a few drops to be put into the M. Fiat collyrium. Sig.- For use eye three or four times daily.
with brush to palpebral conjunctivæ, | and to be washed off with clean water.
Liniments (Linimenta),—are mixtures intended for external application to the skin with friction. The official liniments are solutions of various substances in oily liquids or in alcoholic liquids containing fatty oils, and are enumerated on page 457. Extemporaneous liniments may correspond to the official ones or they may be simple mixtures of fluids without either fat or soap. A prescription for each kind is appended. The official Linimentum Saponis (Soap Liniment) is a good basis for extempo.. raneous preparations of this class. Compound Chloroform Liniment.
Acidi Acetici, . . .
Olei Limonis, . . .
Vitellum, . . .
Aquæ Rosæ, , M. Fiat linimentum.
M. Fiat linimentum. Sig.- Poison. To be rubbed on
Sig.–Liniment. the painful part.
Army Medical Wagon Liniment.
R. Liq. Ammoniæ,
äā, partes æquales. M. Fiat linimentum.
M. Fiat linimentum. Sig.—Poison. Liniment.
Sig.–Liniment. An Embrocation is a similar preparation, but of thinner consistence. The term is almost obsolete.
Injections (Injectiones),-are liquid preparations intended for introduction into the cavities of the body by means of a syringe. When thrown into the rectum they are termed Enemas (Enemata), or Clysters, and are usually prepared at the bedside. Enemata may be demulcent, laxative, nutritive, stimulant, or vermifuge in character; and always have warm or tepid water as their diluent, with which are incorporated such medicaments as may be