Table showing the Drug-strength and the Average Doses of the

A class of powdered extracts, prepared from the extracts by the addition of sufficient Milk Sugar to make the product represent one-half its weight of the crude drug, was official in the U. S. P. VI. (1880) under the title of Abstracts.

The Abstracts have a uniform relation to the drug-viz. I grain represents 2 grains of the drug, just as the fluid extracts have the uniform relation of representing the drug measure for weight.

In preparing an abstract the drug is exhausted, the extract obtained incorporated with its weight of Milk Sugar, the mixture

powdered, and enough Milk Sugar added to bring the product to one-half the weight of the drug employed. Abstracts must be preserved in small, perfectly dry, and well-corked vials in a dry and cool place.

Their uniformity alone should have favored the employment of Abstracts in preference to the Extracts, since they do not share the variability in strength of the extracts, the dose of the Abstract being exactly one-half that of the crude drug or Fluid Extract. This advantage was offset by the disadvantage that Abstracts are more bulky, and caused their deletion in the U. S. P. 1890. The Abstracts are therefore unofficial.

The official Extracts of Jalap and of Nux Vomica have superceded the abstracts of these respective drugs in a more concentrated and equally convenient form. Of the remaining nine Abstracts formerly official, Aconite, Belladonna, Conium, Digitalis, Hyoscyamus (Ignatia, superceded by Nux Vomica), Podophyllum, Senega, and Valerian, the five first mentioned, commonly but erroneously called the "narcotic extracts," may be prepared, in the powdered form, of such strength as to represent the same. drug-strength as their respective official "solid extracts."

EXTRACTUM FERRI POMATUM, N. F.-Ferri Malas Crudus (Ferrated Extract of Apples, Ph. Ger.).

EXTRACTUM GLYCYRRHIZE DEPURATUM, N. F.-Succus Liquiritiæ, Ph. Ger. (Purified Extract of Liquorice).

OLEORESINÆ-OLEORESINS.

To natural Oleoresins, derived as plant-exudations, belong the Turpentines and the Pitches. From similar exudations are obtained the Gum Resins, mixtures of Gum and Resins and sometimes Volatile Oils; also the Balsams, which are Resins or Oleoresins associated with Benzoic or Cinnamic Acid. These are treated under their respective Drugs.

The pharmaceutical Oleoresins are semi-liquid extracts, obtained by exhausting oleoresinous drugs with Ether.

Ether extracts fixed and volatile oils from drugs, as well as resin; these principles constitute therefore the oleoresins, which sometimes also contain other active matter in solution or suspension.

The menstruum (Ether), being easily volatilized, is recovered by distillation; it is sometimes superseded by Alcohol, which yields an extract very similar to that obtained with ether.

The official Resins may be divided into the (1) Natural Resins, (2) Resins obtained from Oleoresins by separating the Volatile Oil by distillation, and (3) the Pharmaceutical Resins, prepared by precipitation.

When a concentrated tincture of a resinous drug is poured into a large quantity of cold water, the resinous matter becomes insoluble and is precipitated; this, after being washed, dried, and sometimes powdered, is termed a resin.

Resins are usually soluble in alkalies and insoluble in acids (dilute); for this reason the water used for precipitation is sometimes rendered slightly acid to favor the separation.

Resina and Resina Copaibæ are obtained as residue in the distillation of the respective Oleoresins, Turpentine and Copaiba. The natural Resins are obtained as exudates-e. g. R. Guaiaci.

The terms resin, resinoid, and concentration are also applied to a class of preparations used by eclectic physicians, prepared by this general process with some modifications. (See U. S. and Am. Disp.)

They are named after their respective Drugs with the ending in, as in Glucosides, and must not be confused with the latter. While the Glucosides are usually the active medicinal constituents representing the drug, the resinoids, with the exception of those made.

from drugs whose active principles are resins, such as Cimicifuga and Podophyllum, are more or less inert, unreliable mixtures, too indefinite in their composition and strength for medicinal use.

SOLID MIXTURES FOR INTERNAL USE.

MIXTURES of Solids for internal use embrace the following classes of preparations: Powders, Effervescent Salts, Confections, Troches, Masses, and Pills.

Powders are substances reduced to a fine pulverulent condition to favor their administration and solution or absorption. A powder may be simple, such as a powdered drug, Pulvis opi, or a powdered salt-i. e. Quinine sulphas; or it may be compound, a mixture of several substances.

Sparingly soluble substances, when finely powdered (impalpable) and thoroughly mixed by trituration in a mortar with some inert powder (diluent) such as Milk Sugar, are rendered more soluble, since a greater surface is exposed to the solvent action of the liquids of the body, and prompter and fuller effects are obtained. The potency of calomel, of the resins, and of alkaloids is in this way considerably increased within certain limits, but not to the unreasonable extent advocated by Homœopathic pharmacy, in which this process is carried to a reductio ad absurdum. It is an excellent and convenient method for dispensing and administering the more potent agents, such as arsenous acid, mercury compounds, and the alkaloids. Substances triturated in this way have been called Triturations, for whose preparation the U. S. P. gives a general formula:

Take of the substance, for example, Elaterin .
Milk Sugar, in fine powder . .

I Gm .9 Gm.

First thoroughly triturate the medicinal substance (Elaterin) with an equal weight of Milk Sugar, then add the remainder of the Milk Sugar, and mix thoroughly by trituration (for about ten minutes).

Unless otherwise specified, triturations should be of the official strength-i. e. 10 per cent. of the drug.

By the addition of about an equal weight of Alcohol to the triturate it becomes a soft mass, which, after being moulded into

disks of about I grain (0.06) each, after the evaporation of the Alcohol, furnishes the so-called Tablet Triturates. These afford a convenient method of medication for such substances as are adapted to trituration, which is, however, confined, as indicated, to a comparatively limited number of agents. To represent in the form of these tablets every kind of medicinal agent of volatile character, or drugs otherwise susceptible to change through the inevitable exposure to the atmosphere to which every such mixture is liable, is simply to invite error in practice. These tablets, moreover, with certain chemical substances, undergo chemical changes which render them entirely insoluble, and thus practically inert. In order to be effective and otherwise reliable, they should be prepared extemporaneously by the pharmacist, in order to ensure their solubility.

They should always be dissolved in a little water before they are administered.

When it is desired to obtain a mild and prolonged local effect of a medicinal agent in the mouth or throat, the substance is made into a soft mass (confection) with a diluent and excipient, Sugar and Mucilage, and flavor, and formed into round or oval-shaped disks, weighing from 8 to 30 grains (1 to 2 Gm.), called variously Lozenges, Troches, Tablets, and Pastils.

Troches.-When these are allowed to dissolve slowly in the mouth the diluent serves as a vehicle for the medicinal agent, and a gradual prolonged effect is obtained upon the mucous surfaces. This form of medication is adapted only to astringents, antacids, expectorants, and stomachics consisting of substances not especially disagreeable to the palate.

Tablets, or Lozenges, are not intended to be swallowed, nor adapted to exceedingly volatile, caustic, irritant, or otherwise unpalatable substances. For ingestion, medicinal agents should be made into a Mass (massa) with an excipient, and formed into small spheres, or balls, as a rule not over 5 grains (0.3) in weight, to be swallowed and slowly dissolved in the stomach or intestines. Such preparations are the so-called Pills (Pilulæ, from pila, ball).

PULVERES-POWDERS.

The nine official Powders are impalpable mixtures of one or more active drugs, usually with some nearly inert substance, such as Sugar, as a diluent, and Aromatics.

They are made by trituration.