Effervescent tablets citric acid

Citric acid (as either the monohydrate or anhydrous material) is widely used in pharmaceutical formulations and food products, primarily to adjust the pH of solutions. It has also been used experimentally to adjust the pH of tablet matrices in enteric-coated formulations for colon-specific drug delivery. Citric acid monohydrate is used in the preparation of effervescent granules, while anhydrous citric acid is widely used in the preparation of effervescent tablets.Citric acid has also been... 

The use of effervescent combinations in this approach the tablet is manufactured and an effervescent mixture (citric acid and. sodium bicarbonate) is introduced into the tablet core via the delivery orifice. Following permeation of water into the tablet core, effervescence occurs that causes a suspension of drug to be dispensed from the delivery orifice (a. 165). 

Mylanta Liquid—simethicone, sorbitol Nephrox Liquid—aluminum hydroxide, mineral oil Original Alka-Seltzer Effervescent Tablets—sodium bicarbonate, aspirin, citric acid, phenylalanine Riopan Plus—magaldrate, simethicone, sorbitol, sucrose Riopan Plus Suspension—magaldrate, simethicone, saccharin, sorbitol... 

Effervescence these systems that consist for instance of a carbonate or bicarbonate salt and an organic acid like e.g. citric acid, develop carbon dioxide gas on contact with water and are well known in pharmaceutical/health food tablets. A few market products exist that make use of this system but for reasons explained above this system is not that suitable for detergent tablets with a high content of surfactants. 

Effervescent tablets disintegrate by virtue of the chemical reaction occurring in water between component ingredients, such as sodium bicarbonate and citric or tartaric acid, to achieve release of carbon dioxide. 

Dorhout Mees EJ, Basci A. 1991. Citric acid in calcium effervescent tablets may favour aluminum intoxication. Nephron 59 322. 

Tablet disruption following production of carbon dioxide is another mechanism used to enhance disintegration. This uses a mixture of sodium bicarbonate and a weak acid such as citric acid or tartaric acid and is exploited for effervescent formulations.

An effervescent mixture of citric acid and sodium bicarbonate was incorporated in a tablet core coated with ethyl cellulose. The carbon dioxide development after water penetration into the core resulted in a pulsatile release after rupture of the coating, which was strongly dependent on the mechanical properties of the coating layer The weak and nonllexible ethyl cellulose film ruptured sufficiently when... 

Lozenges These are compressed tablets formulated, without a disintegrant and must be allowed to dissolve in the mouth. They are used for local activity (throat lozenges) or for systemic effect (vitamins). Effervescent tablets These tablets undergo quick dissolution of actives in water due to internal liberation of carbon dioxide. By combining alkali metal carbonates or bicarbonates with tartaric or citric acid, carbon dioxide is liberated when placed in water. 

Soluble, effervescent tablets are prepared by compression. In addition to active ingredients, they contain mixtures of acids (citric acid, tartaric acid) and sodium bicarbonate (NaHCOs) that release carbon dioxide when dissolved in water. The United States Pharmacopeia (USP) 24 includes the following seven monographs Acetaminophen for Effervescent Oral Solution Aspirin Effervescent Tablets for Oral Solution Potassium Bicarbonate Effervescent Tablets for Oral Solution Potassium Bicarbonate and Potassium Chloride for Effervescent Oral Solution Potassium Bicarbonate and Potassium Chloride Effervescent Tablets for Oral Solution Potassium and Sodium Bicarbonates and Citric Acid for Oral Solution and Potassium Chloride, Potassium Bicarbonate, and Potassium Citrate Effervescent Tablets for Oral Solution. ... 

A comparison of the formation of carbon dioxide from effervescent tablets based on anhydrous citric acid, ascorbic acid or tartaric acid, and NaHCOs in stoichiometric proportions indicated that ascorbic acid and anhydrous citric acid behaved similarly. 

Ascorbic acid can be used as the acid source. The speed of release of carbon dioxide from a mixture of ascorbic acid and NaHCOs is comparable with that produced by citric or tartaric acid-NaHCOs combinations. Since ascorbic acid is less hygroscopic than citric and tartaric acid, using ascorbic acid as the only acid source makes it possible to produce effervescent tablets in a non-airconditional area. ... 

Codeine phosphate in a paracetamol-codeine effervescent tablet was found to react at room temperature with the citric acid constituents to form citrate esters of codeine. The esterification was confirmed in a solid-state reaction at an elevated temperature. Tartaric acid also yielded an ester with codeine phosphate in a similar non-solvolytic reaction. 

Effervescent granules can be tableted while still damp since moist citric acid acts as a lubricant. The compressed tablets are transferred immediately and continuously to ovens where they are dried. Drying also hardens them. " ... 

Effervescent tablets were produced using four different formulations that contained citric and/or tartaric acid and NaHCOs with polyvidone and PEG 6000. The adhesion of each formulation to the metal faces of the punch tips was determined by means of electron microscopy, surface-roughness measurements, and quantification of punch-weight variations during tablet production. The basic formulations were inherently adhesive and produced tablets with a weak, porous structure the tablets were rougher than conventional, non-effervescent compressed tablets. Both formulations that contained tartaric acid produced tablets with a lower surface roughness and had less... 

Potassium and sodium bicarbonates and citric acid effervescent tablets, USP... 

Malic acid is used in pharmaceutical formulations as a general-purpose acidulant. It possesses a slight apple flavor and is used as a flavoring agent to mask bitter tastes and provide tartness. Malic acid is also used as an alternative to citric acid in effervescent powders, mouthwashes, and tooth-cleaning tablets. 

As an excipient, potassium bicarbonate is generally used in formulations as a source of carbon dioxide in effervescent preparations, at concentrations of 25-50% w/w. It is of particular use in formulations where sodium bicarbonate is unsuitable, for example, when the presence of sodium ions in a formulation needs to be limited or is undesirable. Potassium bicarbonate is often formulated with citric acid or tartaric acid in effervescent tablets or granules on contact with water, carbon dioxide is released through chemical reaction, and the product disintegrates. On occasion, the presence of potassium bicarbonate alone may be sufficient in tablet formulations, as reaction with gastric acid can be sufficient to cause effervescence and product disintegration. 

Effervescent tablets are a special group in this category. Processing is identical to compressed tablets except for the addition of sodium carbonate during and citric acid after granulation. 

Verain and coworkers (3) described the formulation of an effervescent paracetamol tablet dosed at 500 mg, containing saccharose and sorbitol as diluents. Other components were anhydrous citric acid, sodium or potassium bicarbonate, PVP, and sodium benzoate. The tablets were characterised by measurement of a number of responses, in particular the friability, the volume of carbon dioxide produced per tablet when it is put in water, and the time over which the tablet effervesced. The objective was to study the effects of 4 factors, the quantities of sorbitol and of citric acid per tablet, the nature of the bicarbonate (whether sodium or potassium bicarbonate), and the effect of different tableting forces on these responses. The... 

Sodium bicarbonate is also used in a number of pharmaceutical applications. For example, it is a common ingredient in antacids, products designed to relieve heartburn, acid indigestion, sour stomach, and other discomforts caused by overeating or improper foods. Some pharmaceuticals, such as Alka-Seltzer , contain a combination of citric acid and sodium bicarbonate. The citric acid helps the sodium bicarbonate dissolve more quickly and produces more effervescence when the tablet is dissolved in water. 

Pi (CH30+ Casa ) allows reading the pH which is 2.63. In effervescent tablets ASA is usually mixed with ascorbic acid, sodium dihydrogencitrate and citric acid, as well as with sodium hydrogen carbonate and disodium carbonate. If a tablet containing only 400 mg ASA and 240 mg vitamin C is dissolved in 150 mL water (this corresponds to 0.0148 mol ASA and 0.009 mol vitamin C) one can describe the solution with the help of the pH-logc, diagram shown in Fig. 66. 

Because of these disadvantages, baking soda is disappearing from medicines. It is still used in effervescent tablets combined with some sohd organic acid (citric acid or tartaric acid), which form carbon dioxide bubbles with baking soda. 

The powder or compressed tablets (effervescent bonbons) are used for preparation of artificial sparkling lemonades. They contain sodium bicarbonate and an acid component (lactic, tartaric or citric acid). When dissolved in water, they generate carbon dioxide. Other constituents of the product are sucrose or another sweetener, and nat-... 

Effervescent Tablets of Potassium, B.P.C. Each tablet contains 500 mg of potassium bicarbonate, 300 mg of potassium acid tartrate with anhydrous citric acid, sucrose and saccharin. 

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