Properties and Uses. - Antacid, mild laxative; valuable for children as well as adults.

Unoff. Preps.: Liquor Magnesii Bicarbonatis, Fluid Magnesia (Br.), 2 p. c. Dose, ℥ j-2 (30-60 Ml. (Cc.)). Mistura Carminatava (Dalby's), 6.5 p. c, + potassium carbonate .3, tinct. opium 2.5, oils of caraway, fennel, peppermint, each .05, syrup 16, water q. s. 100. Mistura Magnesiae, Asafcetidae et Opii (Dewees' Carminative) 5 p. c, + tinct. asafetida 7.5, tinct. opium 1, sugar 10, water q. s. 100.

Properties and Uses. - Antacid, cathartic, antilithic; heartburn, dyspepsia, pregnant vomiting, nauseated stomach with acidity, excessive uric acid secretion, warts, gout; where potassium and sodium salts disagree; externally as a dusting powder in intertrigo, etc., as a cosmetic.

Magnesii Oxidum. Magnesium Oxide, MgO. - (Syn., Mag. Oxid., Magnesia, Calcined Magnesia, Light Magnesia, Light Magnesium, Magnesia Calcinata; Br. Magnesia Levis; Fr. Magnesie, Magnesie calcinee; Ger. Magnesia usta, Gebrannte Magnesia.)

Manufacture: Heat official magnesium carbonate to low redness; water and carbon dioxide escape, leaving magnesium oxide - 4(MgCO3), Mg(OH)2, 5H2O + red heat = 5MgO + 6H2O + 4CO2. It is a white very bulky, fine powder, odorless, earthy but not saline taste, on exposure slowly absorbs moisture and carbon dioxide, insoluble in alcohol, almost so in water, soluble in dilute acids; contains not more than 10 p. c. of water, and after ignition, 96 p. c. of magnesium oxide, 2 p. c. of calcium oxtde. Tests: 1. Dissolve in diluted hydrochloric acid, add ammonium chloride T. S., an excess of ammonia water, sodium phosphate T. S. - white crystalline precipitate. Impurities: Heavy metals, iron, soluble salts, carbonate, water. Should be kept in well-closed containers. Dose, antacid, gr. 5-20 (.3-1.3 Gm.), after meals; purgative, 3ss-l (2-4 Gm.), added to milk or water; infants, gr. 4 (.26 Gm.).

Preparations. - 1. Extracts - as a diluent and dryer. 2. Ferri Hydroxidum cum Magnesii Oxido, 1 p. c. 3. Fluidextractum Cascarae Sagradae Aromaticum, 12.5 p. c. 4. Pulvis Rhei Compositus, 65 p. c.

Properties and Uses. - Like the carbonate; antacid, laxative; dyspepsia, nauseating headache, gout, gravel, heartburn, flatulence, sour eructation, diarrhoea, aphthae, hemorrhoids, infantile colic, warts, ulcers, abrasions.

Magnesii Oxidum Ponderosum. Heavy Magnesium Oxide, MgO. - (Syn., Mag. Oxid. Pond., Heavy Magnesia, Magnesia Ponderosa, Heavy Calcined Magnesia; Fr. Magnesie Calcinee pesante; Ger. Schwere gebrannte Magnesia.)

Manufacture: Same process as magnesium oxide, except here the heavy carbonate is heated instead of the light carbonate, may triturate magnesium oxide with alcohol for some time, dry and pulverize. It is a white, dense, very fine powder; three and a half times heavier than magnesium oxide, and does not, like that, unite readily with water to form gelatinous hydroxide. Should be kept in well-closed containers. Dose, gr. 5-40 (.3-2.6 Gm.).

Liquor Magnesii Citratis. Solution of Magnesium Citrate. - (Syn., Liq. Mag. Cit.; Fr. Limonade au Citrate de Magnesie, Limonade purgative Citro-magnesienne; Ger. Magnesiumcitratlosung, Flussige Citronensaure Magnesia.)

Manufacture: Dissolve citric acid 33 Gm. in hot water 150 Ml. (Cc), add magnesium carbonate 15 Gm., previously mixed with water 100 Ml. (Cc), stir until dissolved, add syrup 60 Ml. (Cc), heat to 100° C. (212° F.), add immediately oil of lemon .1 Ml. (Cc), previously triturated with purified talc 5 Gm., filter, while hot, into a strong bottle, add boiled water q. s. 350 Ml. (Cc); stopper with purified cotton until cold, drop in potassium bicarbonate 2.5 Gm., immediately stopper securely; shake bottle occasionally until dissolved; contains in each 100 Ml. (Cc) magnesium citrate corresponding to 1.5 Gm. of magnesium oxide. Impurities: Tartaric acid, sulphate. Should be kept cool, preferably in a refrigerator, with bottle on its side. Pose, for purge, 1 bottle; as a laxative, 1/2 bottle.

Allied Salts:

1. Magnesii Sulphas Effervescens. Effervescent Magnesium Sulphate, official 1900-1910. - Obtained by heating slowly magnesium sulphate, crystals, 50 Gm. until it ceases to lose weight, pulverizing, mixing with citric acid 13.6 Gm., tartaric acid 21.1 Gm., sodium bicarbonate 40.3 Gm., heating in oven at 93-104° C. (199-219° F.), manipulating with wooden spatula until moist, rubbing through No. 6 tinned-iron sieve, drying granules at 54° C. (129° F.). Similar to magnesium sulphate. Should be kept in well-stoppered bottles. Dose, 3ij-8 (8-30 Gm.).

2. Magnesii Carbonas Ponderosus. Heavy Magnesium Carbonate (Br.). Dissolve magnesium sulphate 125 Gm. and sodium carbonate 150 Gm., each in water 250 Ml. (Cc), mix solutions, evaporate to dryness, digest residue for half an hour with distilled water 500 Ml. (Cc), collect insoluble matter on calico filter, wash out with distilled water soluble sodium sulphate, dry. Dose, gr. 5-60 (.3-4 Gm).

3. Magnesii Citras Effervescens. Effervescent Magnesium Citrate. - Obtained by mixing magnesium carbonate 10 Gm. + citric acid 30 Gm. with distilled water 4 Ml. (Cc), drying, powdering, mixing with sugar 8 Gm., sodium bicarbonate 34 Gm., citric acid 16 Gm., moistening with alcohol, rubbing through No. 6 tinned-iron sieve. It is a white, coarsely granular salt, odorless, mild acid, refreshing taste, deliquescent, soluble with effervescence in 2 parts water, insoluble in alcohol. Impurities: Tartrate, etc.; should be kept in well-closed vessels. Similar to liquor magnesii citratis, being more portable but not so pleasant. Dose, 3j_3 (4 12 Gm.).

4. Magnesii Chloridum. Magnesium Chloride, MgCl2. - Obtained by acting on magnesium carbonate with diluted hydrochloric acid, evaporating. It is in colorless, transparent crystals, white, translucent pieces, deliquescent, soluble in water (.6), alcohol. Dose, 3 ij - 6 (8-24 Gm.).