Buccal administration

Buccal administration is a topical route of administration by which particular drugs held or applied in the buccal () area (in the cheek) will diffuse through the oral mucosa—(tissues that line the mouth)—and will thereby enter directly into the bloodstream. Buccal administration may provide better bioavailability of some drugs and a more rapid onset of action compared to oral administration because the medication does not pass through the digestive system and thereby avoids first pass metabolism. The forms of drugs suitable for buccal administration include tablets and thin films. As of May, 2014, those medications commercially available in buccal forms included the following: the psychiatric drug asenapine; the opioid drugs buprenorphine, naloxone, and fentanyl; the cardiovascular drug nitroglycerin; the nausea medication prochlorperazine; the hormone replacement therapy testosterone; and nicotine as a smoking cessation aid; as was midazolam, an anticonvulsant used to treat acute epileptic seizures. Buccal administration of vaccines has been studied, but there are challenges to this approach due to immune tolerance mechanisms that prevent the body from overreacting to immunogens encountered in the course of daily life.