(1) Pharmaceutical:—
Lead Plaster (Emplastrum plumbi) is simply a lead soap, in which the lead is combined with oleic and margaric acids, and contains some mechanically included glycerin.
Lead Iodide, PbI2, is contained in the Emplastrum plumbi iodidi to the extent of 10 per cent., and in the Unguentum plumbi iodidi to the extent of about 12·5 per cent.
Acetate of Lead is contained in a pill, a suppository, and an ointment. The pill (Pilula plumbi cum opio) contains 75 per cent. of lead acetate, and 12·5 per cent. of opium, the rest confection of roses. The suppository (Suppositoria plumbi composita) contains 20 per cent. of acetate of lead, and 6·6 per cent. of opium, mixed with oil of theobroma. The ointment (Unguentum plumbi acetatis) contains 20·6 per cent. of lead acetate, mixed with benzoated lard.
The solution of subacetate of lead (Liquor plumbi subacetatis) is the subacetate, Pb(C2H3O2)2PbO, dissolved in water; it contains nearly 27 per cent. of subacetate.
A dilute solution of the stronger, under the name of Liquor plumbi subacetatis dilutus, and commonly called Goulard water, is prepared by mixing 1 part (by volume) of the solution and 1 part of spirit, and 78 parts of distilled water; the strength is equal to 1·25 per cent.
There is an ointment, called the Compound Ointment of subacetate of lead, which contains the subacetate in about the proportion of 2 per cent. of the oxide, the other constituents being camphor, white wax, and almond oil.
Carbonate of Lead.—The ointment (Unguentum plumbi carbonatis) should contain about 12·5 per cent. of the carbonate, and the rest simple ointment.
(2) Quack Nostrums, &c.:—
The quack medicines composed of lead are not very numerous.