The oral cavity is an attractive site for the delivery of drugs. The oro-mucosal membrane is readily accessible to patients and/or carers, the high vascularisation can promote a faster onset of action and can reduce or avoids the hepatic and intestinal degradation mechanisms.
The oral mucosa is the mucous membrane of the oral cavity, which includes the tongue, cheeks, palate and gums. Drug delivery within the oral mucosal cavity is classified into five categories:
- local delivery, which is drug delivery into the oral cavity;
- sublingual delivery, which is systemic delivery of drugs through the mucosal membranes lining the floor of the mouth;
- buccal delivery, which is drug administration through the mucosal membranes lining the cheeks (buccal mucosa);
- lingual delivery is drug administration over the tongue; and
- gingival delivery is drug administration through the gums.