This was formerly prepared by heating together sulphuret of antimony and the shavings of hartshorn, or of bones, until the sulphur of the sulphuret, and the organic matters of the horn or bone were completely dissipated, and there was left a mixture of phosphate of lime from the latter source, and oxidized antimony resulting from the combination of atmospheric oxygen with the metal. But the degree of oxidation of the antimony in this process was not precise, varying with the shorter or longer continuance, or the degree of heat, and the preparation was, therefore, necessarily uncertain. As the object aimed at was to procure a mixture of oxide of antimony and phosphate of lime, the British Pharmacopoeia has rejected the old formula, and prepares the powder by simply mixing one part of the antimonial oxide and ten parts of precipitated phosphate of lime, thus giving to the preparation a precision before wanting.

In the old preparation, the greater portion of the antimonial ingredient was in the form of antimonious acid; and sometimes it was exclusively so, the oxide being entirely wanting. In the present, the oxide of antimony (teroxide) is in fixed proportion; and, as the efficiency of the powder depends probably exclusively on this, the phosphate of lime being quite inert, the strength of the preparation is known.

Properties

Antimonial powder is white, inodorous, tasteless, and almost wholly insoluble in water.

Effects on the System

These are precisely the same as those of tartar emetic, but somewhat more slowly induced, and much more uncertain. As the virtues of the preparation depend exclusively on the oxide, and as the activity of the oxide depends on the presence of an acid in the stomach, the action of the powder upon the system must vary with the state of that organ.

Therapeutic Application

The powder as formerly prepared was intended as an imitation of a celebrated secret medicine, known by the name of James's powder, after its original proprietor, which was at one time much used in Great Britain in the treatment of fever; and the antimonial powder, which was contrived by Dr. Pierson, of London, as a substitute, came into use upon the strength of the reputation of the former preparation. It has been given chiefly as a diaphoretic, or emeto-cathartic, in the treatment of fever and rheumatism; and has sometimes been employed as an alterative in diseases of the skin. The dose of the present officinal powder, which is greatly to be preferred, is from three to eight grains, repeated every three or four hours, until it proves diaphoretic, or operates on the stomach or bowels. It may be administered in pill, bolus, or powder mixed with syrup.