Antacids magnesium hydroxide

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. 

Let s begin with a conceptual example by considering the salt magnesium hydroxide, Mg(0H)2, which is a common ingredient in many over-the-counter antacids. Magnesium hydroxide is somewhat soluble in water, has a = 5.61 xlO and maintains the following equilibrium ... 

Antacids Magnesium hydroxide is an ingredient in some antacids. Antacids react with excess hydrochloric acid in the stomach to relieve indigestion. 

The solubility product constant for the antacid magnesium hydroxide (Mg(OH)2) provides another example. 

Antacids are neutralizing agents. Examples are magnesium hydroxide, magnesium trisylicate and aluminium hydroxide. Prior to the introduction of histamine-H2 receptor antagonists and proton pump inhibitors, they were the standard drugs for the treatment of duodenal/ peptic ulcers. Today their clinical use is limited to the treatment of dyspepsia and the symptomatic relieve for patients with peptic ulcers. 

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. 

Sometimes, the body needs some help regulating its acid-base balance. People who experience heartburn, for example, may resort to taking an antacid to neutralize the stomach acid creeping up their esophagus. One popular antacid, milk of magnesia, is actually magnesium hydroxide. The reaction between stomach acid and milk of magnesia is a neutralization reaction ... 

In pharmacology, the term milk refers to an aqueous suspension of a water-insoluble drug. The antacid milk of magnesia contains a saturated solution of the salt magnesium hydroxide. Magnesium hydroxide does not dissolve readily in water, and a saturated solution of this substance simply means that so much... 

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. 

Milk of Magnesia is an alkaline (basic) water suspension and creamy-like suspended form of magnesium hydroxide, MglOH). It is used as an antacid to neutralize excess stomach acid. Magnesium can also be used in the form of Epsom salts as a treatment for rashes and as a laxative. A more important commercial use of Epsom salts is in the tanning of leather, as well as in the dyeing of fabrics. 

Magnesium hydroxide [Mg(OH)j] is a whitish sohd and when suspended in water is used as an antacid known as milk of magnesia. 

Aluminum Hydroxide + Magnesium Hydroxide (Maalox) [OTC] [Antacid/Aluminum Magnesium Salts] Uses Hyper-acidity (peptic ulcer, hiatal hernia, etc) Action Neutralizes gastric acid Dose Adults. 10-20 mL or 2-4 tabs PO qid or PRN Feds. 5-15 mL PO qid or PRN Caution [C, ] Disp Tabs, susp SE May cause t Mg in renal insuff, constipation, D Interactions In addition to AlOH, X effects OF digoxin, quinolones, phenytoin, Fe supl, ketoconazole EMS None OD May cause constipation, loss of appetite, painful urination, heart rhythm changes, muscle weakness, and peripheral edema symptomatic and supportive... 

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. 

These antibiotics are partially absorbed from the stomach and upper gastrointestinal tract. Food impairs absorption of all tetracyclines except doxycycline and minocycline. Absorption of doxycycline and minocy-cbne is improved with food. Since the tetracyclines form insoluble chelates with calcium (such as are found in many antacids), magnesium, and other metal ions, their simultaneous administration with milk (calcium), magnesium hydroxide, aluminum hydroxide, or iron will interfere with absorption. Because some of the tetracyclines are not completely absorbed, any drug remaining in the intestine may inhibit sensitive intestinal microorganisms and alter the normal intestinal flora. 

Acids and bases are among the most familiar of all chemical compounds. Acetic acid in vinegar, citric acid in lemons and other citrus fruits, magnesium hydroxide (milk of magnesia) in commercial antacids, and ammonia in household cleaning products are among the acids and bases that we encounter every day. Hydrochloric acid is... 

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. 

Milk of magnesia, which can be taken as an antacid medicine, is a base. The chemical name for milk of magnesia is magnesium hydroxide (Mg(OH)2). Magnesium hydroxide can ease the discomfort caused by too much stomach acid. Potassium hydroxide (KOH) and sodium hydroxide (NaOH) are also bases. These chemicals, sometimes called lye, and are used in making soap. Sodium hydroxide is also an ingredient of oven and drain cleaners. Bases feel slippery and have a bitter taste. 

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