Drug delivery via the buccal mucosa

A candidate drug has entered the development phase but there are problems in drug delivery. The oral bioavailability is low or provides the wrong plasma profile. It is usual that other routes of administration ave proposed such as nasal, pulmonary, transdermal, buccal or rectal drug delivery. These routes offer advantages but they also require some development time. The situation regarding patents has to be examined, specific formulations must be manufactured - which can require a large amount of the active drug - and sometimes new excipients are used and these have to be documented, and other animal species may need to be chosen for appropriate evaluation. The buccal mucosa is one of the administration sites that might provide an alternative for peroral administration. This review will provide an insight into this route of drug delivery and the formulations that are, or can be, used, and it will also describe the challenges or possibilities of this route of administration.