Calcii Phosphas Praecipitatus (Calc. Phos. Praec.), Precipitated Calcium Phosphate, N.F.—Ca3(PO4)2.

A bulky, white, odorless, tasteless powder. Practically insoluble in water and insoluble in alcohol.

Action and Uses: Precipitated calcium phosphate has been given in the form of powders or mixtures for its action as a calcium salt, which is similar to but without advantage over the action of the carbonate. Because of its insolubility it is now seldom used.

Uses: Similar to but without advantage over the carbonate.

Dosage: 1 Gm. or 15 grains (N.F.).

Syrupus Calcii Hydrochlorophosphatis (Syr. Calc. Hydrochlorophos.), Syrup of Calcium Hydrochlorophosphate, N.F. (Syrupus Calcii Chlorhydrophosphatis, N.F. III).—Precipitated calcium phosphate (1.75%) flavored with tincture of lemon peel and dissolved in hydrochloric acid, water and syrup.

Dosage: 4 Cc. or 1 fluidrachm (N.F.).

Calcii Sulphidum Crudum (Calc. Sulphid. Crud.), Crude Calcium Sulphide, U.S.P. (Calx Sulphurata, U.S.P. VIII, Sulphurated Lime).—CaS (not less than 55%).

A pale gray or yellowish powder, with a faint hydrogen sulphide odor and a nauseous, alkaline taste. Very slightly soluble in cold water, insoluble in alcohol.

Action and Uses: Externally, depilatory similar to barium sulphide. Internally has been used to arrest and prevent suppuration especially in boils, carbuncles and pustular acne. There is no reliable evidence of its therapeutic usefulness.