The buccal cavity is considering as a door for the digestive system. It is composed of teeth,
tongue, and palate. When the food enters the buccal cavity, it is moved along the pharynx and esophagus and
then go onward through the stomach, small intestine, large intestine, and anal opening. When the drug is taken
by the buccal delivery system, it decreases the time needed for the drug to give its action, progresses the
therapeutic action of the drug and gives a better enzymatic flora for drug absorption. It provides direct entry of
drug into the systemic circulation; therefore, decrease all the drawbacks of the per-oral administration of drugs
as hepatic first-pass effect, pre-systemic elimination of GIT by enzymatic degradation; between different routes
of drug delivery, wafers are considered the most advantageous dosage form that taken orally and gives response
at once with little side effects. The buccal region is one of the most convenient and easily approachable routes
for administration of the therapeutic agents to be used locally and systemically.
