Magnesium carbonate dosing

After consulting the physician, phenobarbital dose is reduced to 0.025 g. 1800 mg powder of simethicone from 12 tablets, 300 mg of phenobarbital powder, 1200 mg of magnesium carbonate powder from two tablets and 600 mg of lactose are needed for the 12 capsules. Size of the capsules is 1. 

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... 

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. 

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 used as an excipient in oral solid-dosage pharmaceutical formulations and is generally regarded as an essentially nontoxic and nonirritant material. However, the use of magnesium salts, such as magnesium carbonate, is contraindicated in patients with renal impairment. In addition, the probable oral lethal dose in humans has been estimated at 0.5-5.0g/kg body weight. ... 

In 10 healthy subjects an antacid containing aluminium/magnesium hydroxide and magnesium carbonate reduced the AUC of a single 50-mg dose of captopril by about 40%, when compared with the fasting state. However, this did not alter the extent of the reduction in blood pressure. ... 

Sodium bicarbonate 700 mg or 1.4 g increased the rate of absorption of a single 300-mg dose of naproxen in 14 healthy fasted subjects, whereas magnesium oxide or aluminium hydroxide 700 mg had the opposite effect, and reduced the rate of absorption. Magnesium carbonate had little effect. On the other hand when 15 or 60 mL of aluminium/magnesium hydroxide (Maalox) was given, the rate and extent of absorption of naproxen were slightly increased. ... 

In 12 healthy, fasted subjeets the AUC of a single 50-mg dose of indomet-aein was redueed by 35% when formulated with 80% Merge/ (an antacid formulation of aluminium/magnesium hydroxide, and magnesium carbonate) and by 18% when taken with 90%Merge/. ... 

Magnesium carbonate 1 g reduced the maximum plasma levels of halofantrine 500 mg by almost 50% in a single-dose study in healthy subjeets. The AUC was also redueed by 28%, but this was not statistically significant. The aetive metabolite of halofantrine, which is equally potent, was similarly affeeted. ... 

Quinapril, formulated as Accupro also contains magnesium carbonate (250 mg in a 40 mg quinapril capsule, 47 mg in a 5 mg capsule). A pharmacokinetic study in 12 healthy subjects investigating the potential interaction between the magnesium carbonate in these capsules and tetracycline found that single doses of both of these formulations of quinapril markedly reduced the tetracycline absorption. The 5 mg and 40 mg quinapril capsules reduced the tetracycline AUC by 28% and 37%, respectively, and the maximum serum levels were reduced by 25% and 34%, respectively. ... 

An oven-dried 100 ml flask with a side arm dosed with a septum is fitted with a magnetic stirring bar and a reflux condenser connected to a mercury bubbler. The flask is cooled to room temperature under nitrogen, charged with 4.36 g (0.025 mol) of adipic acid monoethyl ester followed by 12.5 ml of anhydrous tetrahydrofuran, and cooled to —18° by immersion in an ice-salt bath. Then 10.5 ml of 2.39 m (or 25 ml of 1 m) solution of borane in tetrahydrofuran (0.025 mol) is slowly added dropwise over a period of 19 minutes. The resulting clear reaction mixture is stirred well and the ice-salt bath is allowed to warm slowly to room temperature over a 16-hour period. The mixture is hydrolyzed with 15 ml of water at 0°. The aqueous phase is treated with 6 g of potassium carbonate (to decrease the solubility of the alcohol-ester in water), the tetrahydrofuran layer is separated and the aqueous layer is extracted three times with a total of 150 ml of ether. The combined ether extracts are washed with 30 ml of a saturated solution of sodium chloride, dried over anhydrous magnesium sulfate, and evaporated in vacuo to give 3.5 g (88%) of a colorless liquid which on distillation yields 2.98 g (75%) of ethyl 6-hydroxyhexanoate, b.p. 79°/0.7 mm. 

Numerous substances such as calcium, magnesium, and phosphate, administered to rats and/or mice, have been demonstrated to lead to formation of urinary solids and are listed in Table 19.1. This table includes not only a large number of natural, essential ingredients in om diet, but also a number of substances that are formed from normal intermediary metabolism, such as carbonate, oxalate, cystine, urate, and uracil, which are present in normal urine. Numerous synthetic chemicals also produce urinary solids when administered at very high doses, including agrichemicals (such as sulfosulfuron and Fosetyl-Al), industrial chemicals (such as melamine), and pharmaceuticals (such as sulfonamides, carbonic anhydrase inhibitors, and HIV protease inhibitors). 

Acute lead-poisoning is by no means of as common occurrence aa the chronic form, and usually terminates in recovery. It is caused by the ingestion of a single large dose of the acetate, eubacetate, carbonate, ct of red lead. In such cases the administration of magnesium sulplmte is indicated it enters into double decomposition with the Pb salt to form the insoluble PbSO,. 

Silvery-white metal hexagonal dose-packed structure-Slowty oxidizes in moist air. Available as bars, ribbons, wire and powder, mp 651°. bp 1100°. dM 1,738. Sp heat (20°) 0.245 cal/g. Heat of fusion 88 cal/g. Electrical resistivity 4.46 fiohm-cm, E° (aq) MgJ + /Mg —2.37 V. Reads very slowly with water at ordinary temp, less slowly at 100°. Reacts readily with dil adds with liberation of hydrogen reacts with aq solns of ammonium salts, forming a double salt. Reduces carbon monoxide, carbon dioxide, sulfur dioxide, nitric oxide, and nitrous oxide at a red heat. Burns in air continues to bum in a current of steam. Combines directly with nitrogen, sulfur, the halogens, phosphorus, and arsenic, Reacts with methyl alcohol at 200° giving magnesium methylate. 

Claimed that he reduced magnesium and beryllium with great success by mixing the oxides with carbon, iron and linseed oil to a paste and melting in dosed crucible, obtaining alloys with iron. Stromeyer was mistaken. 

Magnesium trisUicate 5 g in 150 mL of water reduced the absorption of a single 100-g oral dose of nitrofurantoin in 6 healthy subjects by more than 50%. The time during which the concentration of nitrofurantoin in the urine was at, or above 32 micrograms/rtiL (a level stated to be the minimum inhibitory concentration) was also reduced. The amounts of nitrofurantoin adsorbed by other antacids in in vitro tests were as follows magnesium trisilicate and charcoal 99%, bismuth subcarbonate and talc 50 to 53%, kaolin 31%, magnesium oxide 27%, aluminium hydroxide 2.5% and calcium carbonate 0%. ... 

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