Buccal adhesive

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. 

Novel approaches, such as the use of buccal adhesive patches for the systemic delivery of large molecular weight drags, require a huge input of time, effort and money, and are also associated with a large amount of risk. These issues can contribute to significant delay in the development and marketing of a new delivery system and can also make these systems relatively expensive. 

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. 

However, the action of saliva and the continuous swallowing thereof tends to wash away drugs applied to the mucosa, resulting in short retention time and low therapeutic efficacy. Therefore, proper design of a dosage form for use in the oral cavity is necessary [23], and to overcome some of these shortcomings, a buccal adhesive system of drug delivery has been developed and is under continued research for improvement [26,24,25]. 

J.D. Smart, Drug delivery using buccal-adhesive systems, Adv. Drug Delivery Rev., 11, 253-270,1993. 

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... 

Schroten, H., Hanisch, F. G., Plogmann, R., Hacker, J., Uhlenbruck, G., Nobis-Bosch, R., and Wahn, V. (1992). Inhibition of adhesion of S-fimbriated Escherichia coli to buccal epithelial cells by human milk fat globule membrane components A novel aspect of the protective function of mucins in the nonimmunoglobulin fraction. Infect. Immun. 60,2893-2899. 

Korbonits M, Slawik M, Cullen D, Ross RJ, Stalla G, Schneider H, Reincke M, Bouloux P.M, Grossman AB. A comparison of a novel testosterone bioadhesive buccal system, Striant, with a testosterone adhesive patch in hypogonadal males. J Clin Endocrinol Metab 2004 89 2039-43. 

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. 

Bodde, E. H., de Vries, M. E., and Junginger, E. H. Mucoadhesive polymers for the buccal delivery of peptides, structure-adhesiveness relationships. J. Control. Release. 13 225-231, 1990. 

The above procedure was also employed to investigate buccal absorption from the HEMAC experimental delivery device. As in the case of the diffusion cell the drug-loaded disc was positioned on the inner central surface of the buccal mucosa. An impermeable film coated with mucosal adhesive (F-4000, Adhesives Research, Glen Rock, PA) on the periphery was then positioned over the HEMAC disc to prevent dehydration and to secure the device in place on the mucosal surface. The disc was allowed to remain in contact with the mucosa for 4 h before it was removed for quantitation of residual drug content. Blood samples were collected over the same interval as for the saturated solution and processed in the same manner. 

The buccal mucosa comprises an expanse of smooth and relatively immobile surface and thus is ideally suited to the use of retentive delivery systems. In contrast, the sublingual mucosa is unsuitable for adhesive dosage forms for a number of reasons, including ... 

Special formulations are now in development to provide prolonged mucosal adhesion and sustained delivery of drug through the buccal membrane. Such formulations comprise flexible adhesive patches and films. Important features for drug delivery associated with these novel buccal patches include ... 

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