Chewable dosage forms

Because of their special properties and advantages, Softgels are used extensively in many pharmaceutical, cosmetic, and nutritional products. The primary pharmaceutical applications include oral dosage forms, chewable Softgels, suppositories, and topical products. 

Drug absorption is highly variable in neonates and infants [21,22]. Older children appear to have absorption patterns similar to adults unless chronic illness or surgical procedures alter absorption. Differences in bile excretion, bowel length, and surface area probably contribute to the reduced bioavailability of cyclosporine seen in pediatric liver transplant patients [22a]. Impaired absorption has also been observed in severely malnourished children [22b]. A rapid GI transit time may contribute to the malabsorption of carbamazepine tablets, which has been reported in a child [23]. Selection of a more readily available bioavailable dosage form, such as chewable tablets or liquids, should be promoted for pediatric patients. 

Both solid and liquid dosage forms may contain saccharin. Saccharin is a nonnutritive sweetening agent, which is 300 times as sweet as sucrose. In a survey of sweetener content of pediatric medications, seven out of nine chewable tablets contained saccharin (0.45-8.0 mg/tablet) and sucrose or mannitol. Seventy-four of the 150 liquid preparations investigated contained saccharin (1.25-33 mg/5 mL) [62], Saccharin is a sulfanamide derivative that should be avoided in children with sulfa allergies [54],... 

Because of the high incidence of lactose intolerance in the general population, lactose is not recommended as a sweetener for pediatric populations [70]. Aspartame, a phenylalanine derivative, is incorporated in many chewable tablets and sugar-free dosage forms. Aspartame-containing products should be avoided in children with autosomal recessive phenylketonuria [54]. 

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. 

Smell, taste, texture, and aftertaste, therefore, are important factors in the development of pediatric dosage forms. In a study of six brands of OTC chewable vitamins, flavor type and intensity, soft texture, and short aftertaste were critical factors in product preference. The flavor and texture attributes of the bestselling product were significantly different from the other brands [97]. 

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]. 

There are many trade-name products for calcium carbonate (e.g., Calel-D, Caltrate, Os-Cal). Only calcium carbonate alternative dosage forms (i.e., chewable, liquid, power) are specifically listed. 

Kraemer J. Chewable Tablets and Chewing Gums. Workshop on Dissolution Testing of Special Dosage Forms, Frankfurt, March 05, 2001 (oral presentation). 

Tablets are solid dosage forms that are compressed or prepared by a sintering proeess, including sublingual, buccal, chewable, effervescent, and compressed tablets. Some of these ean be easily compoimded an example of a tablet triturate is as follows ...

A drug product is a finished dosage form (e.g., tablet, capsule, or solution) that contains a drug substance, generally, but not necessarily, in association with one or more other ingredients [21 CFR 314.3(b)]. A solid oral dosage form includes tablets, chewable tablets, capsules, and soft gelatin capsules. 

Carbopol resins also have been used in controlled-release dosage forms. Especially, the resins Noven AA-1 USP and Carbopol 934P NF are being extensively developed in bioadhesive drug delivery systems for topical, bucal or nasal, ocular, and rectal applications (e.g., Fentanyl ). Noven CA-1 USP and CA-2 USP are used as oral laxative and antidiarrheal products in swallowable and chewable tablets. 

Mendes, R.W. Anaebonam, A.O. Daruwala, J.B. Chewable tablets. In Pharmaceutical Dosage Forms Tablets, Lieberman, H.A., Lachman, L., Schwartz, J.B., Eds. Marcel Dekker, Inc. New York, 1989 I, 362-387. Richards, R.M. Xing, J.Z. Mackay, K.M. Excipient interaction with cetylpyridinium chloride activity in tablet based lozenges. Pharm. Res. 1996, 13 (8), 1258-1264. 

Taste acceptability is a particular issue with oral liquid dosage forms, lozenges, and chewable tablets. The problem may be overcome by the preparation of poorly soluble salts. Thus the bitterness of erythromycin and of bacitracin may be ameliorated by use of the estolate (lauryl sulfate) and zinc salts, respectively. Propoxaphene may be taste masked by forming the napsylate, the solubility of which may be further reduced and the taste improved by adding a common-ion salt such as sodium or calcium napsylate. 

Solid dose forms tablets, capsules and boluses These dosage forms are most commonly for administration to dogs and cats. Capsules and some tablets are swallowed whole. The dosage form is placed on the back of the pet s tongue and its mouth is held shut, thereby forcing ingestion. Chewable formulations are often, treat-like formulations and may be swallowed whole, chewed, or... 

There have also been several references to the use of carrageenan in chewable tablets having a confectionary texture.This approach to creating a novel dosage form requires the use of both i-carrageenan and K-carrageenan, to prevent moisture loss and texture changes that occur over time. 

Daruwala J. Chewable tablets. In Liebetman H. Lachman L. eds. Pharmaceutical Dosage Forms Tablets. New YorK Marcel Dekker, IrK, 1980 289-337. 

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