Adhesive tablets, buccal

Biphasic buccal adhesive tablets have also been used for smoking cessation therapy with nicotine [83]. 

Park, C.R., and D.I. Munday. Development and evaluation of a biphasic buccal adhesive tablet for nicotine replacement therapy. Int J Pharm 237 215. 

Yong et ah [175] developed an effective omeprazole buccal adhesive tablet with excellent bioadhesive force and good drug stability in human saliva. The omeprazole buccal adhesive tablets were prepared with various bioadhesive polymers, alkali materials, and croscarmellose sodium. Their physicochemical properties, such as bioadhesive force and drug stability in human saliva, were investigated. The release and bioavailability of omeprazole delivered by the buccal adhesive tablets were studied. As bioadhesive additives for omeprazole tablet, a mixture of sodium alginate and hydroxypropylmethyl cellulose was selected. The omeprazole tablets prepared with bioadhesive polymers alone had bioadhesive forces suitable for a buccal adhesive tablet, but the stability of omeprazole in human saliva was not satisfactory. Magnesium oxide is an alkali stabilizer for omeprazole buccal adhesive tablets. Croscarmellose sodium enhanced the release of omeprazole from the tablets but it decreased the bioadhesive forces and stability of omeprazole tablets in human saliva. 

Buccal dosage forms can be of the tablet, patch, gel, or ointment type and can be employed for local or systemic delivery. For local deliveiy, conventional dosage forms such as solutions and various types of tablets (immediate release, effervescent, etc.) are more suitable. These forms generally have uncontrolled drug release with subsequent variable absorption and short residence times, and may not provide sufficient bioavailability. Novel dosage forms such as adhesive tablets, patches, gels, and... 

Because of their excellent adhesion and physiological safety, povidone K 30 and povidone K 90 are used as adhesives on the skin or mucous membranes. Examples include transdermal systems, oral adhesive gels, buccal adhesive patches or tablets [511,546,547,559,573,574], contact gels for electrocardiograph or electroencephalograph electrodes and adhesives for colostomy bags. Table 107 shows a formulation for a contact gel developed on a laboratory scale for ultrasonic scanning. 

Buccal mucoadhesive tablets are mostly intended for systemic use, but adhesive tablets and semisolid forms can also be used to obtain a local effect. 

Sustained adhesion of the dosage form (tablet, patch) to the mucosa is an important first step to successful buccal delivery. The mucus plays an important role during this mucoadhe-sive process by buccal drug delivery systems. The interaction between the mucus and mucoadhesive polymers generally used in most dosage forms can be explained by theories summarized in Table 9.1. 

Hu F, Wang H, Wu X. Effects of different adhesives on the stability of vitamin C buccal tablets. Zhejiang Yike Daxue Xuebao 1997 26 108-110. 

A bio-adhesive material used in the preparation of buccal tablets was prepared using roller compaction (20). A fractional factorial design was employed to investigate... 

A typical basic formulation of a mucoadhesive buccal tablet is given in Table 182. In this case the adhesive effect of copovidone was much higher than the adhesion of povidone K 30 or povidone K 90. 

The strength of mucoadhesion of the tablets was quantified based on the tensile force required to break the adhesive bond between a model membrane, i.e., porcine buccal mucosa and the test pol5mier. The study revealed that locust bean gum and chitosan in a weight ratio of 2 3 not only releases the drug unidirectionally from the dosage form, but also results in buccal tablets which are sufficiently mucoadhesive for clinical applications (34). 

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