Effervescent tablet formulations

Rotthauser, B., Kraus, G., and Schmidt, P. C. (1998), Optimization of an effervescent tablet formulations containing spray-dried L-leucine and polyethylene glycol 6000 as lubricants using a central composite design, Eur. J. Pharm. Biopharm., 46, 85-94. 

Rotthauser, B. Kraus, G. Schmidt, P.C. Optimization of an effervescent tablet formulation containing spray dried... 

Fumaric acid is used primarily in liquid pharmaceutical preparations as an acidulant and flavoring agent. Fumaric acid may be included as the acid part of effervescent tablet formulations, although this use is limited as the compound has an extremely low solubility in water. It is also used as a chelating agent which exhibits synergism when used in combination with other true antioxidants. 

It is used in food products, primarily to adjust the pH of solutions. It is also used as a sequestering agent. The anhydrous material is used in effervescent tablet formulations. Sodium citrate is additionally used as a blood anticoagulant either alone or in combination with other citrates such as disodium hydrogen citrate. 

G. Roscheisen, PC. Schmidt, Preparation and optimization of 1-leucine as lubricant for effervescent tablet formulations, Pharmaceutica ACTA Helvetiae, 70,133-139,1995. 

Effervescent Tablets. Effervescent tablets are another means of supplying medications to the elderly. This type of formulation provides the patient with an easy-to-swallow product that is aesthetically pleasing (i.e., forms a clear solution, rather than a cloudy... 

P. Merckle and K.A. Kovar, Assay of effervescent tablets by near-infrared spectroscopy in transmittance and reflectance mode acetylsalicylic acid in mono and combination formulations, J. Pharm. Biomed. Anal, 17, 365-374 (1998). 

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. 

The bioavailability of an effervescent ibuprofen tablet was compared to a sugar-coated tablet. Ibuprofen was absorbed more rapidly from the effervescent tablet but both formulations were bioequivalent in... 

Twenty lubricants for effervescent tablets were tested for lubrication efficiency in direct compression of a standard effervescent formulation. The lubricant concentration was high as compared to traditional tablet lubricants. By increasing the lubricant concentration... 

The use of binders will normally prevent a rapid dissolution of the effervescent tablet. Therefore, many effervescent tablets are formulated without any binder. However, effervescent granules may be formulated with binders since their large surface area, when compared withthat of the conventional or the effervescent tablet, will result in rapid dissolution. An effervescent... 

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... 

The disintegration and dissolution times are very important characteristics of effervescent products. A well-formulated effervescent tablet will disintegrate and dissolve within 1-2 min to form a clear solution. Consequently, the residue of undissolved drug must be minimal. The temperature of the water influences the dissolution time. It is, therefore, important to choose a water temperature that is actually used by consumers (e.g., cold tap water). Ph. Eur. includes a general requirement on disintegration time of 5 min in water 15-25°C.t ... 

Saleh, S.I. Aboutaleb, A. Kassem, A.A. Stamm, A. A contribution to the formulation of effervescent tablets by direct compression. Labo-Pharma Probl. Tech. 1984, 32,163-166. 

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... 

Fumaric acid has been investigated as a lubricant for effervescent tablets and copolymers of fumaric acid and sebacic acid have been investigated as bioadhesive micro-spheres. " It has been used in film-coated pellet formulations as an acidifying agent and also to increase drug solubility. ... 

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. 

Many solid-dosage forms of potassium chloride exist including tablets prepared by direct compression and granulation effervescent tablets coated, sustained-release tablets " sustained-release wax matrix tablets micro-capsules pellets and osmotic pump formulations. ... 

Sodium bicarbonate is generally used in pharmaceutical formulations as a source of carbon dioxide in effervescent tablets and granules. It is also widely used to produce or maintain an alkaline pH in a preparation. 

Tablets may also be prepared with sodium bicarbonate alone since the acid of gastric fluid is sufficient to cause effervescence and disintegration. Sodium bicarbonate is also used in tablet formulations to buffer drug molecules that are weak acids, thereby increasing the rate of tablet dissolution and reducing gastric irritation. ...

Povidone K 25 and povidone K 30 are very good binders for effervescent tablets, as they dissolve rapidly in water to form a clear solution. This particularly applies to effervescent vitamin tablets, e.g. ascorbic acid tablets [368 b]. Tables 65 and 66 give formulations for ranitidine effervescent tablets and multivitamin effervescent tablets as typical examples that were developed on a laboratory scale. For the granulation of multivitamin preparations, it is always preferable to use a fluidized bed. 

Table 147 gives a guide formulation developed in the laboratory for effervescent tablets for children, containing 1 g of micronized crospovidone as the active ingredient. No problems are to be expected with the chemical stability of this formulation. However, moisture-proof packaging is recommended, to stabilize the physical properties of the tablets for the duration of their intended shelf-life. 

Table 147. Formulation of crospovidone effervescent tablets (lab scale) [615] ...

Table 3.7 Experimental Domain for the Formulation of an Effervescent Tablet...

The exclusive use of aspirin is as a medicine. It has three important properties as a drug. It relieves pain, reduces inflammation, and reduces fever. In addition to its effectiveness in treating these medical symptoms, it is inexpensive and available in a variety of forms, including chewable tablets, extended-release formulations, effervescent tablets, and even in chewing gums. Aspirin is often prescribed in low, daily doses as a preventative measure for individuals at risk for heart attack and stroke. 

---