Chewable tablet formulations

Saccharin is an intense sweetening agent used in beverages, food products, table-top sweeteners, and oral hygiene products such as toothpastes and mouthwashes. In oral pharmaceutical formulations, it is used at a concentration of 0.02-0.5% w/w. It has been used in chewable tablet formulations as a sweetening agent. 

Parameters reported for the didanosine chewable tablet formulation. 

Knupp CA, Milbrath R, Barbhaiya RH. Effect of time of food administration on the bioavailability of didanosine from a chewable tablet formulation. J Clin Pharmacol (1993) 33, 568-73. 

Finally, another unique formulation is a chewable tablet available to women who have difficulty swallowing medications. Ovcon 35 (norethindrone/ethinyl estradiol) has all 28 tablets in chewable form and has added spearmint flavoring.30 Along with each of these unique oral contraceptives, there are preparations currently being studied that contain 24 active pills and 4 placebo pills per pack, shortening the hormone-free period.1... 

Chewable tablets and sprinkle capsule formulations have been very well received by both patients and their parents for use in children with full dentition (older than 3 years, [75-77]. This is potentially a very fruitful area for future research and development. Pharmaceutical preparations developed for administration to young children need to have consistent bioavailability when administered with food [78]. 

The dosage forms most commonly employed for pediatric formulations are liquids and chewable tablets. A perceived unpleasant taste is much more evident with these dosage forms than when a drug is administered as a conventional solid oral dosage form. Second, it is widely believed that children younger than the age of 6 years have more acute taste perception than older children and adults. Taste buds and olfactory receptors are fully developed in early infancy. Loss of taste perception accompanies the aging process. 

Chewable Tablets. It has already been noted that most elderly patients experience a decrease in their ability to chew efficiently [125,137,138,143]. Therefore, by virtue of their design, chewable tablets are not often recommended for use by elderly patients (particularly those who are edentulous) 155-163,164], Most chewable formulations also rely on an adequate amount of chewing action to obtain full release of their ingredients (e.g., chewing promotes the foaming action provided by some chewable antacid products). So, aside from being difficult form the elderly patient to use, full benefit of a chewable dosage form may not be achieved by these patients. Additionally, the use of chewable tablets by denture wearers may cause local irritation in the oral cavity [155]. 

The every-12-hour regimen is associated with significantly less diarrhea however, the 200 and 400 mg formulations (suspension and chewable tablets) contain aspartame and should not be used by phenylketonurics. 

In pharmaceutical applications, sorbitol is used as a tablet diluent in wet granulation or dry compression formulations. It is commonly used in chewable tablets because of its sweet taste, and it is also used as a plasticizer for gelatin in capsule formulations. Sorbitol is utilized in sugar-free liquid preparations and as a stabilizer for drug, vitamin, and antacid suspensions. When it is used in syrups, crystallization around bottle caps is prevented. 

The original formulation, a buffered powder, has been replaced by chewable and dispersible buffered tablets with greater bioavailability (30-40%) a new enteric-coated formulation further improves patient convenience and tolerability. Since the chewable tablets contain both phenylalanine (36.5 mg) and sodium (1380 mg), caution should be exercised in patients with phenylketonuria and those taking sodium-restricted diets. Didanosine should be taken on an empty stomach and, because of the buffered formulation, should be administered at least 2 hours after administration of drugs requiring acidity for optimal absorption (eg, ketoconazole, itraconazole, dapsone). 

Liquid release. Dose adjustment may be needed. Benefit is less fluctuation of levels. Retard is given as twice daily dosing (rather than three times day for standard). Chewable tablets reach peak plasma concentration more slowly than syrup (6 hours vs. 2 hours) Suitable for long-term use. No clinically relevant difference between oral dose forms. No dose adjustments between oral formulations... 

Some adults, as well as most young children, have difficulty swallowing medications formulated as standard pills (tablets and capsules).When oral medications are needed, drug therapy can be more efficient, and patient compliance improved, by prescribing medications formulated as chewable tablets, solutions, or suspensions, which are usually flavored to improve taste and are easily swallowed. 

Chewable tablets. These tablets are preferred for pediatric and geriatric patients who have difficulty swallowing whole tablets. Another advantage is that they do not need water for administration. Mannitol is normally used as the base diluent because of its pleasant taste and texture, and because it can effectively mask the taste of objectionable actives. They are usually prepared by wet granulation and are not compressed very hard. High amounts of flavor are added to increase palatability. Antacids are typically formulated as chewable tablets. 

Sorbitol is used as a diluent in tablet formulations prepared by either wet granulation or direct compression. It is particularly useful in chewable tablets owing to its pleasant, sweet taste and cooling sensation. In capsule formulations it is used as a plasticizer for gelatin. Sorbitol has been used as a plasticizer in film formulations. ... 

Granulates of xylitol are used as diluents in tablet formulations, where they can provide chewable tablets with a desirable sweet taste and cooling sensation, without the chalky texture experienced with some other tablet diluents. Xylitol solutions are employed in tablet-coating applications at concentrations in excess of 65% w/w. Xylitol coatings are stable and provide a sweet-tasting and durable hard coating. 

The combination of copovidone with sucrose and micro crystalline cellulose is mentioned for vitamin C chewable tablets in the commentary to the German Standard Generic Formulations as show in Table 175 [460]. 

Many oral solutions are intended for pediatric administration, of which oral solution formulations are a subset of a larger choice of formulation type such as suspension, syrup, powder or microcapsules for constitution to a suspension, powder for reconstitution to a solution or suspension, solid particles (powder, coated particles, extended release, enteric-coated granules, beads) in packets or capsules to be sprinkled on food, oral powders, and chewable tablets. The broader topic of pediatric formulation development is beyond the scope of this chapter, but this chapter will cover selected oral solutions for pediatric administration. 

Peak concentrations of didanosine are seen approximately 1 hour after oral administration of the chewable tablets or powder formulations and 2 hours after delayed-release capsules. The plasma elimination half-life of the parent drug is approximately 1.5 hours, but the estimated intracellular half-life of dideoxyadenosine 5 -triphosphate is substantially longer, 25 to 40 hours. As a result, didanosine can be administered once daily. Didanosine is excreted by both glomerular filtration and tubular secretion, and does not undergo metabolism to a significant degree. Drag doses therefore must be adjusted in patients with renal insnfficiency or renal failure. 

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. 

Dosage forms available oral and chewable tablets, suspension, two con-trolled-release formulations (Tegretol-XR, Carbatrol)... 

In other cases, a new dosage formulation is required to satisfy a new market segment. Oral solutions and chewable tablets are beneficial for a pediatric population. A slow-release preparation (such as percutaneous patches) may be preferred in elderly patients taking multiple drugs if it allows once-daily (or less frequent) dosing. Trials demonstrating safety and efficacy of new formulations are often conducted in Phase IV and typically act as the supporting information for an sNDA. 

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