Drug absorption oral cavity mucosa

One of the most common in vivo methods used to assess the permeability of the buccal mucosa is the buccal absorption test of Beckett and Triggs [13]. In this test, a known volume of a drug solution is introduced into the oral cavity of a subject, who swirls it around for a specified period of time and then expels it. The subject then rinses his or her mouth with an aliquot of distilled water or buffer solution, and the expelled drug solution and rinse are combined and analyzed for drug content. The difference between the initial and final drug concentration in the solution is assumed to be the amount of drug taken up into the oral mucosa. 

Of the range of pharmaceutic preparations available for administration into the oral cavity, the most popular form is that of a rapidly dissolving tablet that releases its drug contents for absorption across the oral mucosa. Alternatively, a tablet or capsule can be chewed to release its contents. This latter method is less successful because mastication tends to produce a large volume of saliva that increases the probability of premature swallowing. The same problem occurs in the administration of drug in the form of a chewing gum. 

Mouthwashes, toothpastes and other preparations are introduced into the oral cavity for local prophylactic and therapeutic reasons. It is not known to what extent components of these formulations are absorbed and give rise to systemic effects. The absorption of drugs through the oral mucosa, however, provides a route for systemic administration which avoids exposure to the gastrointestinal system. Dmgs absorbed in this way bypass the liver and have direct access to the systemic circulation. The sublingual, buccal and gingival... 

Suppository is solid-like preparation made from drug and suitable bases for cavity administration. When inserted into cavities, they melt or soften, after which drug dissolution and absorption result in local or systemic effect. Whin rectal suppository is a common form which is usually used as laxatives. Administrated by rectum mucosa, suppositories possess many advantages compared with oral route. Firstly, it is a convenient administration way for infants or patients suffering from vomiting or gastrointestinal disturbances. 

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