EXTEMPORANEOUS PREPARATIONS.

469 tion 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 435. 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 extemporaneous preparations of this class.

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 desired. They may consist simply of water to act as a wash for the cleansing of the bowel. Injections are termed vaginal, urethral, vesical, nasal, hypodermic, etc., according to the locality in which they are employed. A special form of syringe is employed in each case, the discussion of which belongs rather to the domain of surgery than that of medicine. Those used for the nasal cavities are often arranged with small holes or an atomizing attachment, so as to deliver the injection in the form of a fine spray. A Collunarium is a nasal douche or wash. In the Appendix will be found a list of formulæ for hypodermic injections; a few prescriptions for other forms are appended below.

Baths (Balnea), are often medicated, and then become medicinal preparations. The ingredients only are ordered in a prescription, as per the following examples, each of which is intended for a bath of 25 to 30 gallons:

SOLID EXTEMPORANEOUS PREPARATIONS.

Pills (Pilula),—are described on page 438, where also the official pills are enumerated. They constitute a form of medicine very much used in extemporaneous pharmacy, and one with the preparation of which the compounder should be perfectly familiar, for it will constitute fully onethird of his work at the dispensing counter. Pills should not exceed 5 grains in weight, unless the ingredients are very heavy, as Bismuth, Calomel, Hydrargyrum cum Creta, etc., of which 6, 8, or 10 grains may be made into a pill which may be readily swallowed.

EXTEMPORANEOUS PREPARATIONS.

471 A Bolus is a similar mass, but larger than a pill, while the names Granule and Parvule are given to masses smaller than the average pill.

THE PROCESS OF PILL-MAKING is briefly as follows: The ingredients ordered in the prescription are separately weighed out in the order of their bulk, commencing with that one of which the smallest quantity is to be used. If any require pulverization they should first be placed in the mortar, and reduced to powder; then the other dry ingredients, next the soft extracts and the excipient selected, and the whole is worked up into a mass, the Pill-mass, by the aid of the mortar and pestle. The perfect pill-mass should be uniform throughout, should not show any particles of any one ingredient, should have such a consistence that the pills made from it will retain their shape, should not be too hard, nor too dry, nor should it stick to the fingers. The mortar should be large and shallow, of unpolished wedgewood ware; having a thick, smooth and well-formed bottom, and a pestle which fits it. The operation of working up the mass is one of kneading it between the end of the pestle and the side of the mortar, and if proper ingredients and excipient are used, and if the work is well done, the mass will eventually loosen itself from both mortar and pestle. If it does not do so it should be removed with a spatula when sufficiently worked, and may then be kneaded for a few minutes. between the fingers. It should then be placed upon the tile or slab previously dusted with a little Lycopodium or Starch in fine powder, and rolled into a long cylinder by the aid of a broad-bladed spatula, until the mass is of a length corresponding to the divisions on the tile-scale which represent the number of pills to be made. The mass should then be placed along the scale, and a cut made through it with the spatula at each division of the scale, the pieces being at once rounded separately into pills. by the thumb and two fingers of each hand. A pill-machine is often employed, consisting of two metal plates having semi-cylindrical grooves on one side, and set into wooden boards, the whole forming a convenient apparatus for rolling the mass and then cutting it into the required number of pills by one movement. The pills are then left to dry upon the slab while the label is being written, after which they are placed in a pill-box, or in a wide-mouthed bottle if they contain volatile ingredients, and surrounded by a conspergative powder (Lycopodium, powdered Chalk, dusted Talc), to prevent their adhering together or losing their shape.

EXCIPIENTS used in pill-making are seldom mentioned in the prescription, but are usually left to the choice of the compounder. Some substances need no excipient, but may be made at once into pills; such being the softer Extracts and some Gum-resins, the former if too hard only needing a little water, and the latter a few drops of spirit to soften them to the required degree of plasticity. Every druggist has his favorite pill-excipient, many using a paste made of powdered Tragacanth 1, Glycerin

31⁄2 and Water I part, while others use Extract of Malt, or a mixture of Syrup and powdered Acacia, for general use. Powdered Tragacanth to give tenacity, Glycerin to keep the mass soft, and Water to develop the adhesive qualities of many ingredients, will answer for fully nine-tenths of all the cases which occur in practice. These three excipients should stand on the dispensing counter ready for use, and all ready-made pastes or mixtures should be discarded, as being slovenly, dirty, and liable to change. The excipients described below are those in general use, and are arranged in the order of their comparative importance, viz. :

LIQUID EXCIPIENTS.

Glycerin,-is a very valuable excipient, as it continually attracts moisture from the atmosphere, and pills made from it do not get hard. It should be used always for Quinine pills. Glycerites of Starch or Tragacanth are generally useful excipients. The former is official, the latter is made in the proportion of 3 ss to the 3.

Glucose, is a good excipient, being colorless, adhesive, and not readily volatilized at ordinary temperatures. Since its introduction by Mr. Lascheid for this purpose it has steadily grown in favor.

Honey, may be used for dark-colored substances. It should be evaporated to one-half its bulk, and then if mixed with a little Tragacanth, it makes an excellent excipient for insoluble powders.

Extract of Malt,-is a pretty fair excipient, but has the disadvantage of its dark color. Syrup, is a fair excipient for powders, but it should not be used for inetallic salts, especially Calomel, which it reduces in a short time. Syrup of Acacia is good where there is little room left for the excipient, but if kept too long, pills made with it become very hard and insoluble.

Mucilage of Acacia,-is very adhesive, but not a good excipient for the same reason as given for the syrup.

Water, is only used alone as an excipient when the ingredients possess sufficient adhesiveness to be developed by the water. Such are the following powders: Aloes, Rhubarb, Kino, Tannic Acid, Opium, Squill, Asafetida,-also Citrate of Iron, Sulphate of Berberine, etc.

Alcohol, is used to soften Camphor, Compound Extract of Colocynth, Guaiac, resinous extracts, gums, etc.

SOLID EXCIPIENTS.

Tragacanth,-is an excellent excipient, especially for substances which are too soft, giving them body and elasticity.

Acacia,-is added to give more adhesiveness than can be obtained from viscid liquids alone. Pills made with it are generally very hard. It is used for Nitrate of Silver, which may explode if mixed with vegetable extracts or glucose.

Soap,- is the best for resinous and fatty substances, increasing the solubility of the former. It is more employed in the official pills than any other excipient, but should not be used for substances which are decomposed by an alkali, nor for Tartar Emetic.

Bread-crumb (Mica Panis),—is an excellent excipient for Croton Oil, or other powerful liquid substances, as Volatile Oils.

Confection of Rose,-is too bulky for general use, but is a good excipient for very active agents, like Strychnine, which are used in small quantity.

Althea,-is good for absorbing and adhesive purposes, but is too bulky for general use. Petrolatum, Cacao Butter, and Resin Cerate,-are used for oxidizable substances, as Potassium Permanganate.

Kaolin,-is well adapted for Nitrate of Silver, and other substances which are easily decomposed.

Liquorice, is an old excipient, but not much employed now. In powder it may be

used for oils.

CONSPERGATIVES,-are absorbent powders which are dusted upon the

H

EXTEMPORANEOUS PREPARATIONS.

473

finished pills and put around them in the box or vial in which they are dispensed, to keep them from sticking together and losing their shape. Powdered Liquorice was formerly much used for this purpose, but the best conspergatives are Lycopodium, Talc, Althea, and Rice Flour, the latter especially for white pills.

SUBSTANCES SUITABLE for the pilular form of medicine are the following :

Those acting in small doses.
Those intended to act slowly.

Those to act on the lower bowel.

Heavy, insoluble substances.
Fetid substances.

Vegetable extracts.

Gum-resins, Balsams, Turpentine.

When the basis is an unadhesive substance, one of the other ingredients should be an extract or a vegetable powder, which will form a mass by moisture alone. Attention to this rule in prescribing pills will often prevent the increase of their size by inert excipients.

DIFFICULT SUBSTANCES to combine, except by peculiar treatment, are met with frequently. The following notes will cover most of the cases :—

Aloes,-is best treated on a heated slab with alcohol in very small quantity. Soap is the excipient in the official Pilulæ Aloes.

Butyl Chloral Hydrate,-should be treated with a little Confection of Rose and thick mucilage.

Calcium Sulphide,-should be well triturated with an equal quantity of Sugar of Milk, and then worked up with a little powdered Liquorice-root and Tragacanth Mucilage. Camphor, should be powdered with a little alcohol, and may be worked into a pillmass with Glycerite of Tragacanth after the evaporation of the alcohol.

Carbolic Acid,-requires nearly an equal part of wheaten flour or bread crumb, with a very minute quantity of Glycerite of Tragacanth. Creasote may be made into a mass by the addition of powdered Liquorice with a very little bees' wax. If made into a pill with Oxide of Silver it will explode unless the silver salt be first diluted by trituration with Liquorice, Gentian, or some other inert powder.

Citrate of Iron and Quinine,-is very deliquescent with most excipients. Canada Balsam is the best for it.

Copaiba, may be made into pill-mass by the addition of a little Carbonate of Magnesium or Wax.

Croton Oil,-is best worked up with bread-crumb, though powdered Liquorice and mucilage may be used.

Ferrum Iodide,-in pill form requires special manipulation and protection to remain unoxidized. The official Pil. Ferri Iodidi is prepared with Iodine and Reduced Iron, has Liquorice, Sugar, and Acacia as excipients, and is protected by a coating of Balsam of Tolu (see ante, page 221). In other formulæ, Acacia, Althæa, Cocoa butter, Elm-bark, and Liquorice are used as excipients.

Ferri Sulphas,-is used in Blaud's Pill and in the official Pil. Ferri Compositæ, with Carbonate of Potassium, to form by mutual decomposition Ferrous Carbonate, which quickly passes into the ferric salt by exposure. Myrrh in powder and Syrup are the excipients used for the official pill.

Gallic Acid,-makes a good pill with a very small quantity of Glycerin. Tannic Acid requires about one-fifth its weight of Glycerin and one-tenth of Mucilage.

Phosphorus,-presents the problem of combining it in pill without letting it oxidize. This is believed to be accomplished by the pharmacopoeial directions for the Pil. Phosphori, according to which the Phosphorus is dissolved in Chloroform in a test-tube, then quickly worked into a mass with Althæa, Acacia, Glycerin and Water, and finally the pills are coated by shaking with an Ethereal solution of Balsam of Tolu. Carbon Bisulphide is a better solvent, but when it is used the pill-mass retains its disgusting odor.