Antacids calcium carbonate

Flor S, Guay DR, Opsahl JA, Tack K, Matzke GR. Effects of magnesium-aluminum hydroxide and calcium carbonate antacids on bioavailability of ofloxacin. Antimicrob Agents Chemother 1990 34(12) 2436-8. 

Erost RW, Lasseter KC, Noe AJ, Shamblen EC, Lettieri JT. Effects of aluminum hydroxide and calcium carbonate antacids on the bioavailability of ciprofloxacin. Andmi-... 

CaC03 Calcium carbonate Antacid, calcium supplement... 

Calcium carbonate is used in food and pharmaceutical appHcations for both its chemical and physical properties. It is used as an antacid, as a calcium supplement in foods, as a mild abrasive in toothpaste, and in chewing gum to name only a few (see EoOD ADDITIVES). 

Calcium carbonate or magnesium hydroxide antacids may decrease the effectiveness of the digestive enzymes. When administered concurrently with an iron preparation, the digestive enzymes decrease the absorption of oral iron preparations. 

Antacids containing either calcium carbonate or aluminum hydroxide... 

Hyperphosphatemia is generally benign and rarely needs aggressive therapy. Dietary restriction of phosphate and protein is effective for most minor elevations. Phosphate binders such as aluminum-based antacids, calcium carbonate, calcium acetate (PhosLo , Nabi), sevelamer (Renagel , Genzyme), and lanthanum carbonate (Fosrenol , Shire) may be necessary for some patients.43 If patients exhibit findings of hypocalcemia (tetany), IV calcium should be administered empirically. 

Calcium carbonate is the primary component of seashells, antacids, marble and limestone (e.g. stalactites and stalagmites in caves), blackboard chalk, scale in water pipes, and calcium supplements for people and animals. It is also used to capture S02 gas in fossil fuel burning boilers, thereby helping to prevent acid rain, and as a soil additive to provide pH adjustment and calcium to farmers soil. 

Intermittent, mild heartburn Lifestyle modifications plus patient-directed therapy Antacids Maalox or Mylanta 30 mL as needed or after meals and at bedtime Gaviscon 2 tabs after meals and at bedtime Calcium carbonate 500 mg, 2-4 tablets as needed and/or Nonprescription 11 receptor antagonists (taken up to twice daily) Cimetidine 200 mg Famotidine 10 mg Nizatidine 75 mg Ranitidine 75 mg or... 

Single or combination nonprescription antacid products, especially those containing magnesium hydroxide, aluminum hydroxide, and/or calcium carbonate, may provide sufficient relief from simple nausea or vomiting, primarily through gastric acid neutralization. 

Inorganic compounds such as aluminium hydroxide, sodium bicarbonate, and magnesium and calcium carbonates are commonly used as antacids. There is much scope for the redesign of these agents to achieve fine control of local pH values in the gastrointestinal tract via control of the rate of release of the active bases (e.g., from insoluble compounds). 

It may seem strange that we would ever want to perform an experiment of this kind. First of all it would be used in the event of a slow reaction taking place in the reaction flask. Perhaps the sample is not dissolved completely, and addition of the titrant causes dissolution to take place over a period of minutes or hours. Adding an excess of the titrant and back-titrating it later would seem an appropriate course of action in a case of this kind. An example would be the determination of the calcium carbonate in an antacid tablet (Experiment 13). 

Why is a back titration useful in the analysis of an antacid tablet containing calcium carbonate as the active ingredient ... 

Calcium carbonate (CaCO ) can be in the form of an odorless crystal or powder and is one of calcium s most stable compounds, better known in its natural state as limestone, marble, chalk, calcite, oyster shells, and the minerals marl and travertine. Calcium carbonate is the source of lime and is used as a filler for many products, including paints, plastics, and foods (bread), and as an antacid. 

Antacids containing calcium carbonate have the greatest neutralising capacity but tend to cause acid rebound with long-term use. Calcium carbonate may also lead to hypercalcaemia and the milk-alkali syndrome, which is characterised by nausea, headache and renal damage. 

Milk-alkali syndrome Milk-alkali syndrome, an acute illness with symptoms of headache, nausea, irritability, and weakness, or a chronic illness with alkalosis, hypercalcemia and, possibly, renal impairment, has occurred following the concurrent use of high-dose calcium carbonate and sodium bicarbonate. Hypophosphatemia Prolonged use of aluminum-containing antacids may result in hypophosphatemia in normophosphatemic patients if phosphate intake is not adequate. 

Calcium Acetate (PhosLo) [Calcium Supplement/ Anti arrhythmic/Mmeral/ Electrolyte] Uses ESRD-associated hyper-phos-phatemia Action Ca " supl w/o aluminum to X P04 absorption Dose 2-4 tabs PO w/ meals Caution [C, ] Contra t Ca Disp Gelcap SE Can t Ca, hypophosphatemia, constipation Interactions t Effects OF quinidine X effects W/ large intake of dietary fiber, spinach, rhubarb X effects OF atenolol, CCB, etidronate, tetracyclines, fluoroquinolones, phenytoin, Fe salts, thyroid hormones EMS Pts have reduced renal Fxn, monitor ECG for signs of electrolyte disturbances OD S/Sxs of hypercalcemia (confusion, weakness, GI upset, constipation, N, V, and cardiac arrhythmias) give IV fluid for diuresis symptomatic and supportive Calcium Carbonate (TumS/ Alka Mints) [Antacid/ Calcium Supplement/Mineral/ Electrolyte] [OTC] Uses Hyperacidity associated w/ peptic ulcer Dz, hiatal hernia, etc Action Neutralizes gastric acid Dose 500 mg—2 g PO PRN -1- in renal impair Caution [C, ] Disp Chew tabs, susp SE t -1- PO constipation Interactions X Effect OF tetracyclines, fluo-... 

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. 

A variety of adverse effects have been reported following the use of antacids. If sodium bicarbonate is absorbed, it can cause systemic alkalization and sodium overload. Calcium carbonate may induce hypercalcemia and a rebound increase in gastric secretion secondary to the elevation in circulating calcium levels. Magnesium hydroxide may produce osmotic diarrhea, and the excessive absorption of Mg++ in patients with renal failure may result in central nervous system toxicity. Aluminum hydroxide is associated with constipation serum phosphate levels also may become depressed because of phosphate binding within the gut. The use of antacids in general may interfere with the absorption of a number of antibiotics and other medications. 

If the chalk is made of calcium carbonate, CaCO, it is made of the same active ingredient found in many antacids. The calcium carbonate is a base that reacts to neutralize any excess acids. Be careful, though, never to take too much calcium carbonate because the stomach is designed to always be somewhat acidic. 

The physician is concerned with at least three factors when prescribing antacids (1) Acid rebound (associated with calcium carbonate) (2) milk-alkali syndrome (caused by ingestion of large quantities of alkali) and (3) phosphorus depletion (by aluminum salts). The mechanism of add rebound, especially in the long-term use of caldum carbonate, is poorly understood. It has been established that there is an excessive re-addification of the antrum (pylonc gland area) a number of hours after ingestion of calcium caibonate. 

Chalk, A native amorphous calcium carbonate composed of calcareous remains of minute marine organisms. It can be used as antacid or stabilizer in expl and proplnt compns(See Calcium Carbonate, under Carbonates)... 

FIGURE 27-1 T Neutralization of hydrochloric acid [HCI] by the primary forms of antacids. In each reaction, the antacid combines with HCI to form a salt and water. Carbon dioxide [C02] is also produced by calcium carbonate and sodium bicarbonate antacids. 

The primary antacids can be classified as aluminum-containing, magnesium-containing, calcium carbonate-containing, sodium bicarbonate-containing, or a combination of any of these classifications. These drugs are typically taken orally, either as tablets or as a liquid oral suspension. 

Tetracyclines, as broad-spectrum antibiotics, are the drugs of choice in treating Mycoplasma pneumoniae infections. Most tetracyclines are absorbed to various degrees (30 to 100%) from the gastrointestinal tract, primarily from the stomach and upper small intestine. The absorption of tetracyclines is hindered by milk and milk products, by numerous antacids such as aluminum hydroxide, sodium bicarbonate, and calcium carbonate, and by iron preparations such as ferrous sulfate. Therefore, these and similar substances should not be administered orally together with tetracycline (Figure 3.4). 

Calcium carbonate(eg, Turns, Os-Cal) is less soluble and reacts more slowly than sodium bicarbonate with HC1 to form carbon dioxide and CaCl2. Like sodium bicarbonate, calcium carbonate may cause belching or metabolic alkalosis. Calcium carbonate is used for a number of other indications apart from its antacid properties (see Chapter 42 Agents That Affect Bone Mineral Homeostasis). Excessive doses of either sodium bicarbonate or calcium carbonate with calcium-containing dairy products can lead to hypercalcemia, renal insufficiency, and metabolic alkalosis (milk-alkali syndrome). 

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