Antacid, magnesium carbonate

Aideloje SO, Onyeji CO, Ugwu NC. Altered pharmacokinetics of halofantrine by an antacid, magnesium carbonate. Eur J Pharm... 

USP-grade anhydrous magnesium carbonate is used as a flavor impression intensification vehicle in the processed food industry (see Flavors and spices). Basic magnesium carbonates are used as free flowing agents in the manufacture of table salt, as a hulking agent in powder and tablet pharmaceutical formulations, as an antacid, and in a variety of personal care products (see Pharmaceuticals). 

Aluminum Hydroxide + Magnesium Carbonate (Gaviscon Extra Strength/ Liquid) [OTC] [Antacid/Aluminum Magnesium Salts] Uses Relief of heartburn, acid indigestion Action Neutralizes gastric acid Dose Adults. 15-30 mL PO pc hs Peds. 5-15 mL PO qid or PRN avoid in renal impair Caution T Mg (w/ renal insuff) [C, ] Disp Liq, chew tabs SE Constipation, D Interactions In addition to AlOH effects OF histamine blockers, hydantoins, nitrofurantoin, phenothiazines, ticlopidine, T effects OF... 

Drugs that have been associated with elevations in quinidine concentrations include acetazolamide, the antacids magnesium hydroxide and calcium carbonate, and the H2-receptor antagonist cimetidine. Cimetidine inhibits the hepatic metabolism of quinidine. Phenytoin, rifampin, and barbiturates increase the hepatic metabolism of quinidine and reduce its plasma concentrations. 

Two patients with hypothyroidism taking a fixed dosage of levothyroxine took aluminium hydroxide and magnesium oxide (72). In both cases there was a marked increase in the serum concentration of TSH and low serum T4. After withdrawal of the antacids, TSH again fell. In vitro studies showed a dose-related adsorption of levothyroxine by a combination of aluminium hydroxide, magnesium hydroxide, and magnesium carbonate, but no effect of magnesium oxide alone. 

Antacids are gastric-acid neutralizing or adsorbing medications, usually containing aluminium and/or magnesium salts (e.g. aluminium hydroxide, magnesium carbonate, hydroxide or trisilicate), which have the ability to decrease the absorption of several medications that are co-administered (often due to the formation of chelates/insoluble unabsorbable complexes). 

Some antacid mixtures contain sodium, which may not be readily apparent from the name of the preparation. Thus they may be dangerous for patients with cardiac or renal disease. For example, a 10 ml dose of magnesium carbonate mixture or of magnesium trisilicate mixture contains about 6 mmol of sodium (normal daily dietary intake is approx. 120 mmol of sodium). 

Magnesium carbonate is additionally used as a food additive and therapeutically as an antacid. 

On contact with gastric acid, magnesium carbonate reacts in the stomach to form soluble magnesium chloride and carbon dioxide. Magnesium carbonate should therefore not be used as an antacid by those individuals whose stomachs cannot tolerate the evolution of carbon dioxide. Some magnesium is absorbed but is usually excreted in the urine. As with other magnesium salts, magnesium carbonate has a laxative effect and may cause diarrhea. 

Figure 6.20 Adsorption of digoxin by some antacids at 37 0.1°C ( ) magnesium trisilicate, (A) aluminium hydroxide gel BP (Aludrox was used in the concentration range 2.5-10%v/v), (A) light magnesium oxide, (O) light magnesium carbonate, ( ) calcium carbonate. Initial concentration of the glycoside 0.25 mg%.

Antacids often contain carbonates, for example, sodium hydrogen carbonate, calcium carbonate, and magnesium carbonate. A carbonate-containing antacid neutralizes excess stomach acid by reacting with acid to produce carbon dioxide. 

After purification, Mg(OH)2 can be reacted with carbon dioxide to give magnesium carbonate, used for coating sodium chloride in table salt to prevent caking and for antacid remedies. Another alternative is to add hydrochloric acid to the magnesium hydroxide to neutralize it and yield hydrated magnesium chloride ... 

The same principle applies to acid indigestion. Rather than swallow lye (ugh ) or some other strong base to neutralize excess stomach acid, most people take antacids. Antacids typically contain salts such as calcium carbonate, sodium hydrogen carbonate (sodium bicarbonate), and magnesium carbonate, all of which are salts of weak acids. These... 

THERAP Cat Magnesium carbonate hydroxide as antacid, cathartic hydrotaicite as antacid. 

Carbonic acid, magnesium salt (1 1), mixture with magnesium hydroxide (Mg(OH)2), hydrate CCRIS 7884 Magnesium carbonate basic Magnesium carbonate hydroxide Marinco C. A basic magnesium carbonate of variable composition. Used in fireprooSnp, as an antacid and laxative and in manufacture of magnesium compounds. 

Aluminum Hydroxide + Magnesium Carbonate (Gaviscon Extra Strength, Liquid) [OTC] [Antacid/Aluminum ... 

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