Homeopathic medicines are prepared according to the "Homeopathic Pharmacopeia of the United States," which was adopted as the standard in 1897 by the American Institute of Homeopathy. This differs from the U. S. P. in that it provides for but two kinds of liquid preparations. These are tinctures (marked θ) dilutions, or potencies, which are made from the tinctures (marked 2, 3, or higher, or 2x, 3x, etc.). There are two kinds of solid preparations, - triturations and triturations compressed into tablets, called trituration tablets.

Its tinctures exceed in number many times those in the U. S. P., and have this peculiarity, that, wherever possible, they are made from fresh plants gathered at the time of their greatest activity. It is now generally admitted that "therapeutic actions in small doses can be better obtained from preparations which contain the volatile constituents of the plant."

With very few exceptions these fresh plant tinctures (as well as a small number of tinctures which have to be made from dried substances) constitute a uniform ten per cent. drug strength.

This is done by a simple yet ingenious method. A given quantity of a fresh plant is weighed. This is then thoroughly dried and again weighed. The difference in weight represents the plant moisture or juice, and this is considered as so much water in the menstruum. By taking a sufficient quantity of the fresh plant, which, if evaporated, would contain one hundred parts of solids, and by then adding to the plant moisture a sufficient quantity of alcohol as a menstruum, sufficient to produce 1,000 parts of tincture - a tincture of ten per cent. drug strength is obtained. If the season of gathering is a dry one and the plant moisture diminished in consequence, sufficient distilled water is added to the moist plant mass to make it equal the normal weight (the formula for which is given for each drug in the Pharmacopeia). In a wet season, the excess of plant moisture is to be deducted from the menstruum. This may be done by cautiously drying out the moisture until it is reduced to the normal.

Tinctures are prepared by maceration or by percolation. Percolation is mainly used for a comparatively small number of tinctures which have to be made from dried plants. The tinctures are marked θ, and could properly be also marked 1 or lx dilution, on account of their 10 per cent. drug strength.

To obtain the remedy in the potentized form, which experience has shown to be frequently more efficacious than the tincture, one part of the latter is thoroughly shaken with nine parts of the prescribed menstruum of alcohol and distilled water, or with alcohol alone; this constitutes the 2 or 2x dilution, or potency. One part of the 2nd dilution with 9 parts of menstruum and again thoroughly shaken makes the 3rd or 3x dilution, and so on by the same process to the 30th dilution or higher. In what are called the higher potencies ordinary chemical analyses fail to detect any material presence of the original substance and the spirit-like force, to which Hahnemann ascribed the virtue of these preparations, may probably be expressed in these modern times by the terms ionization or electronization. These liquid preparations are administered in various ways. From 4 to 10 drops of a tincture of a dilution may be stirred into 4 ounces of pure water, and given in teaspoonful doses.

For convenience in carrying, the liquids are poured over globules made of pure cane sugar. Disks or cones are also medicated in the same manner as globules.

A so-called tincture-trituration is sometimes used. This is made by adding 10 cubic centimeters of tincture to 10 grammes of milk sugar and rubbing them together in a mortar until thoroughly dry. The only advantage of this method is, that a liquid may be dispensed in a dry form. Its disadvantage is, that volatile constituents are apt to be lost during the process of drying.

Insoluble substances, such as some of the metals, metallic salts, etc., are prepared by trituration with milk sugar, a gritty substance admirably adapted to the purpose of breaking up the drug particles. As in the case of tincture, the strongest trituration is of 1/10 or 10 per cent. drug strength. One part by weight of the drug is triturated with 9 parts by weight of finely powdered milk sugar until the largest drug particles do not exceed 1/500 inch in diameter. This constitutes the first decimal trituration and is marked 1 or lx or 1/10.

One part by weight of this lx trit. is triturated with 9 parts of milk sugar until the largest particles are not over 1/2000 of an inch in diameter, This constitutes the 2x trituration, one grain of which should approximate 1/100 of a grain of the original drug. Some drugs, however, cannot be reduced to this degree of fineness.

The other triturations are to be made in the same manner from the preceding ones. The largest particles of the 3x trituration are not to exceed 1/4000 of an inch in diameter. In the fourth and higher triturations the microscope is not depended upon; but the same degree of trituration is given in each case, as was required to reduce the particles in the 2x trituration to the 1/2000 of an inch.

The Homeopathic Pharmacopeia of the United States contains a number of tests of triturations. Remedies have been triturated up to the 30x, and this is the preferred method for the preparation of all insoluble substances.

Sometimes dilutions are prepared from triturations. These are made by dissolving 1 grain of the 6x trituration in 50 minims of distilled water and then adding 50 minims of alcohol. After thorough shaking this is marked the 8x dilution. Subsequent potencies are prepared from this in the same manner as has been described under "dilutions." As a rule, however, the Pharmacopeia's direction, that insoluble substances are better reserved for trituration, is the best to follow.

The dose of a trituration is commonly said to be as much as will cover a dime, or from two to three grains, dry on the tongue. Triturations are compressed into tablets which contain 1 or 2 grains. These have the advantage of a definite dosage.

Homeopathic medicines are, therefore, very largely prepared on the decimal scale. The solid and liquid preparations are approximately the same in drug strength. They are prescribed singly, never by mixing two or more remedies. Alternation of remedies, i. e., the administration of first one and then another remedy, and so on, is a practice not to be recommended.

Compound tablets, i. e., those composed of more than one remedy, are not recognized in the Homeopathic Phamacopeia.