Sodium bicarbonate with aspirin

The most frequently adverse reactions are those involving the Gl tract (e.g., abdominal pain, discomfort, and nausea) but appear to be less than those observed with aspirin. The CNS effects (e.g., dizziness and drowsiness) also are observed. Few cases of overdosage have been reported, but in such cases, recommended treatment includes elimination of the drug from the Gl tract by emesis or gastric lavage and elimination of the acidic drug from the circulatory system by enhancing alkalinization of the urine with sodium bicarbonate. 

In the preparation of many pharmaceuticals we know that some components in the formulation are not compatible. For instance, if we mix acetyl salicylic acid with sodium bicarbonate in solution, there is an immediate reaction and a vigorous release of carbon dioxide. Nevertheless, it might be of interest to freeze-dry them together in order to have instant sparkling aspirin, but this is not possible and the only way around this is to compact the products together in the dry state. The resulting tablet is not very stable and it takes a relatively long time to get back into solution. 

Aspirin can be separated from many other organic substances in chloroform solution by extraction with sodium bicarbonate solution. 

The answer is a. (Hardman, pp 16-20.) Sodium bicarbonate is excreted principally in the urine and alkalinizes it. Increasing urinary pH interferes with the passive renal tubular reabsorption of organic acids (such as aspirin and phenobarbital) by increasing the ionic form of the drug in the tubular filtrate. This would increase their excretion. Excretion of organic bases (such as amphetamine, cocaine, phencyclidine, and morphine) would be enhanced by acidifying the urine. 

As mentioned in the historical synopsis (Section 5.1), Levine121 perfected the compendial partition column procedure in which aspirin in chloroform is first trapped in an immobile phase of sodium bicarbonate on a column of siliceous earth (celite) then eluted with a solution of acetic acid in chloroform and measured spectrophotometrically. This has been also used for separation in combination products.80 For the determination of salicylic acid in presence of aspirin by this method, see Section 5.61. Ion exchange columns filled with strongly or weakly basic anion exchange resin in the acetate or chloride cycle have also been used for separation of aspirin in combination products. 122 123/l2lf This has also been adapted for a student experiment.125 A Sepha-dex-G25 column has been used for the separation of aspirin from salicylic acid.126... 

The antipyretic and analgesic actions of aspirin are believed to occur in a certain area of the brain. It is also thought by some that the salicylates exert their analgesia by their effect on water balance. Aspirin is anti-inflammatory because it inhibits the biosynthesis of chemicals called prostaglandins. The irritation of the stomach lining caused by aspirin can be alleviated with the use of mild bases such as sodium bicarbonate, aluminum glycinate, sodium citrate, aluminum hydroxide, or magnesium trisilicate (a common trademark for this type of aspirin is Bufferin ). 

The irritation of the stomach lining caused by aspirin can be alleviated with the use of mild bases such as sodium bicarbonate, aluminum glyci-nate, sodium citrate, aluminum hydroxide, or magnesium trisilicate (a trademark for this type of aspirin is Bufferin ). 

Test the solubility of your sample in toluene and in hot water and note the peculiar character of the aqueous solution when it is cooled and when it is then rubbed against the tube with a stirring rod. Note also that the substance dissolves in cold sodium bicarbonate solution and is precipitated by addition of an acid. Compare a tablet of commercial aspirin with your sample. Test the solubility of the tablet in water and in toluene and observe if it dissolves completely. Compare its behavior when heated in a melting point capillary with the behavior of your sample. If an impurity is found, it is probably some substance used as binder for the tablets. Is it organic or inorganic To interpret your results, consider the mechanism whereby salicylic acid is acetylated. 

Treatment for salicylate intoxication is directed toward (1) decreasing further absorption, (2) increasing elimination, and (3) correcting add-base and electrolyte disturbances. Activated charcoal binds aspirin and prevents its absorption. Elimination of salicylate may be enhanced by alkaline diuresis and in severe cases by hemodialysis." Sodium bicarbonate may be given to alleviate metabolic acidosis. Indications for hemodialysis include serum salicylate >1000 mg/L, severe CNS depression, intractable metabolic acidosis, hepatic failure with coagulopathy, and renal failure. ... 

Recommendations for sodium bicarbonate vary (from class 1 to class in) depending on the clinical situation. Sodium bicarbonate use is acceptable for patients with known, preexisting hyperkalemia (class 1), preexisting bicarbonate-responsive acidosis (class 11a), overdoses of tricychc antidepressants (class 11a), and to aUcalinize the urine in aspirin and other drug overdoses (class 11a). In addition, sodium bicarbonate may be of benefit in intubated and ventilated patients with along arrest interval (class 11b). Sodium bicarbonate may be harmful in hypercarbic acidosis, and patients with this condition should not receive it (class IH). 

The acid-ether extract is shaken with a solution of sodium bicarbonate to remove the strong acids such as aspirin, then with sodium hydroxide solution to remove the weak acids, such as the barbiturates, neutral drugs such as the carbamates, and a few weak bases such as calFeine, remaining in the ether layer. 

APC tablets are a mixture of aspirin, phenacetin, and caffeine. Each of these substances has characteristic absorption in the ultraviolet region, with the principal maxima lying at 277 nm for aspirin, 275 nm for caffeine, and 250 nm for phenacetin. In the procedure, a powdered tablet is dissolved in methylene chloride, and the aspirin is separated from the phenacetin and caffeine by extracting it into aqueous sodium bicarbonate solution. The separated aspirin is back-extracted into methylene chloride by acidifying the aqueous layer and is then measured spectrophoto-metrically at 277 nm. The phenacetin and caffeine that remain in the original methylene chloride layer are determined in mixture as described in Chapter 16 (Equations 16.16 and 16.17). 

Pharmaceutical Incompat, (from Remington s Pharmaceutical Sciences) Aspirin forms a damp to pasty mass when triturated with acetanilide, phenacetin, antipyrine, amidopyrine, methenamine, phenol or phenyl salicylate. Powders containing aspirin with an alkali salt such as sodium bicarbonate become gummy on contact with atmospheric moisture. Hydrolysis oecnrs in admixture with salts contg water of crystallization. Solns of the alkaline acetates and citrates, as well as alkalies themselves, dissolve aspirin but the result -ing solns hydrolyze rapidly to form salts of acetic and salicylic acids. Sugar and glycerol have been shown to hinder this decompn. Aspirin very slowly liberates hydriodic acid from potassium or sodium iodide. Subsequent oxidation by air produces free iodine. 

Alka-Seltzer contains sodium bicarbonate, potassium bicarbonate, citric acid, and aspirin. The fizz of the Alka-Seltzer tablet in water is carbon dioxide gas given off by the reaction of the citric acid with the bicarbonates to give carbonic acid (the preceding reaction). 

Sodium bicarbonate, sold as baking soda, can be dissolved in water directly and taken as an antacid. It can also be purchased as Alka-Seltzer, a combination of sodium bicarbonate, citric acid, and aspirin. The citric acid reacts with some of the bicarbonate ions to produce gaseous CO2, the familiar fizz ... 

Alka-Seltzer tablets contain aspirin, sodium bicarbonate, and citric acid. When they come into contact with water, the sodium bicarbonate (NaHCO ) and citric acid (H3C6H5O7) react to form carbon dioxide gas, among other products. 

A Alka-SeltzerTM contains sodium bicarbonate mixed with citric acid and aspirin. When put in water, the acid and carbonate react. 

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