Aspirin Antacids

A medicinal product on the general sale list is a product that can be sold or supplied over-the-counter at any retail outlet. Examples include paracetamol preparations, antacids, aspirin. GSL products are considered to be relatively safe and can be freely purchased by the public. 

Over-the-counter (OTC) Available to anyone Antacids, aspirin, most cough medicines... 

Several colorless household solutions sueh as vinegar, lemon juice, other fruit juices, window cleaners, soaps, shampoos, and detergents and common household products such as baking soda, antacids, aspirin, salt, and sugar... 

Food containing salicylate (curry powder, paprika, licorice, prunes, raisins, and tea) may increase the risk of adverse reactions. Coadministration of the salicylates with activated charcoal decreases the absorption of the salicylates. Antacids may decrease the effects of the salicylates. Coadministration with the carbonic anhydrase inhibitors increases the risk of salicylism. Aspirin may increase the risk of bleeding during... 

Each Alka-Seltzer tablet contains 1916 mg of sodium bicarbonate, 1000 mg of citric acid (Fig. 9.1.2), and 325 mg of aspirin or acetylsalicylic acid (Fig. 9.1.3). Bromo Seltzer also contains sodium bicarbonate and citric acid as well as acetaminophen (Fig. 9.1.4). Several equilibria describe the action of bicarbonate-based antacid tablets. First of all, sodium bicarbonate dissolves completely in aqueous solution to generate sodium ions and bicarbonate ions ... 

Drugs that may interact include antacids, cimetidine, aspirin, digoxin, phenytoin, and theophylline. 

ASPiRiN, BUFFERED The addition of small amounts of antacids may decrease Gl irritation and increase the dissolution and absorption rates of these products. Dosing is the same as with unbuffered aspirin. 

Drugs that may affect aspirin include activated charcoal, ammonium chloride, ascorbic acid or methionine, antacids and urinary alkalinizers, carbonic anhydrase inhibitors, corticosteroids, and nizatidine. Drugs that may be affected by aspirin include alcohol, ACE inhibitors, anticoagulants (oral), beta-adrenergic blockers, heparin, loop diuretics, methotrexate, nitroglycerin, NSAIDs, probenecid and sulfinpyrazone, spironolactone, sulfonylureas and exogenous insulin, and valproic acid. 

Conversely, certain drugs modify the effectiveness or side effects of aspirin. Phenobarbital, occasionally used for seizures, induces liver enzymes that increase the metabolism and excretion of aspirin, (3-adrenoceptorblocking drugs, such as propranolol, and decrease the antiinflammatory effects of aspirin, whereas reserpine decreases its analgesic effects. Antacids decrease the absorption of aspirin. Alcohol consumption in combination with aspirin increases the latter s ulcerogenic effects. 

Paget s disease PO 400 mg once a day for 3 mo. Must takewith6-8oz plain water. Do not give within 2 hr of food intake. Avoid giving aspirin, calcium supplements, mineral supplements, or antacids within 2 hr of tiludronate administration. 

The reactions in Table 13.8 show that carbon dioxide is a common product in many neutralization reactions. This is clearly displayed when a drop of vinegar (acetic acid) is added to baking soda (sodium bicarbonate). Some aspirin includes an antacid in their formulation to neutralize some of the acidity imparted by the aspirin (acetylsalicylic acid). These are commonly referred to as buffered aspirins. 

Many aspirins are advertised as buffered aspirin, and this has led to the misunderstanding that these aspirin are buffers. In reality, as mentioned previously, buffered aspirins actually contain an antacid to reduce the problems brought on by the effects of aspirin, which is the acid called acetylsalicylic acid. Because of its widespread use and importance to humans, let s take an extended look at the history and chemistry of aspirin. 

Aspirin s original use as an analgesic, antipyretic, and to reduce inflammation continues to this day, and more recently some evidence has been found that it may lessen the chance of heart attacks due to its effect as a blood thinner. Just as aspirin continues to provide the same benefits as a century ago, it also produces some of the same problems. The major problem is that it can upset the stomach. In the acidic environment of the stomach, aspirin can diffuse through the protective mucous lining of the stomach and rupture cells and produce bleeding. Under normal doses, the amount of blood loss in most individuals is only a milliliter or two, but in some individuals who take heavy doses bleeding can be severe. To counterattack this side effect, manufacturers include an antacid such as aluminum hydroxide and call the aspirin a buffered aspirin. As noted previ-... 

Aluminum compounds are used in many diverse and important industrial applications such as alums in water-treatment and alumina in abrasives and furnace linings. They are found in consumer products such as antacids, astringents, buffered aspirin, food additives, and antiperspirants. Powdered aluminum metal is often used in explosives and fireworks. To learn more about the properties and uses of aluminum, see Chapters 3 and 4. 

Aluminum compounds are also used extensively in the manufacture of cosmetics (e.g., aluminum hexahydrate in deodorants) and in medical treatments (e.g., aluminum hydroxide in antacids to control gastric hyperacidity or aluminum oxide in dental ceramic implants) (Brusewitz 1984 NRC 1982). In addition, antacids and buffered aspirin contain 4-562 mg/kg (ppm) of aluminum (Schenck et al. 1989 Shore and Wyatt 1983). Lione (1985a) reported aluminum content/dose (single tablet or 5 mL liquid) for antacids, internal analgesics (buffered aspirins), antidiarrheals, and anti-ulcerative drugs (Table 5-7). 

As with adults, aluminum intake from aluminum-containing medication, such as antacids, buffered aspirins, and antidiarrheal agents would overwhelm ordinary dietary intakes (Pennington and Schoen 1995). Children may also be exposed to aluminum from vaccinations, parenteral feeding of premature infants, dialysis fluids, and treatment for hyperphosphatemia. 

As discussed in Section 5.4.4, individuals consuming large quantities of antacid formulations, anti-ulcerative medications, buffered analgesics, or antidiarrheal medications are exposed to higher than background doses of aluminum in their diet. Lione (1985a) estimated that from 126 to 728 mg and 840 to 5,000 mg were possible daily doses of aluminum consumed in buffered aspirins for rheumatoid arthritis and antacid products, respectively. These doses are from 6 to 40 times and 42 to 250 times greater, respectively, than aluminum doses obtained from consumption of foods (20-24 mg/day). 

For example, aspirin should be avoided in patients with ulceration and patients taking anticoagulation medications. It is possible that misuse or overdose of OTC products may develop into many medical problems. For example, improper use of antacids (e.g., aluminum hydroxide) causes constipation. 

---