Origin. - Prepared by evaporating to dryness the mixed solutions of magnesium sulphate and sodium carbonate, and purifying and drying the residue.

Description and Properties. - Light, white, friable masses, or a light, white powder, without odor, and having a slightly earthy taste; permanent in the air. Almost insoluble in water, to which, however, it imparts a slightly alkaline reaction; insoluble in alcohol, but soluble in diluted acids, with active effervescence.

Dose. - As an antacid, 5-20 grains (0.3-1.3 Gm.) [44 grains (3 Gm.), U. S. P.].

Official Preparation

Liquor Magnesii Citratis - Liquoris Magnesii Citratis - Solution of Magnesium Citrate. - A liquid of magnesium carbonate, citric acid, and potassium bicarbonate, widely used as a pleasant laxative.

Dose. - 2-12 ounces (60-360 Cc).

Magnesii Sulphas - Magnesii Sulphatis - Magnesium Sulphate.

See Cathartics.