Oral administration is a route of administration whereby a substance is taken through the mouth, swallowed, and then processed via the digestive system. This is a common route of administration for many medications.

Oral administration of a liquid. In pharmacology and toxicology, a route of administration is the way by which a drug, fluid, poison, or other substance is taken into the body. Routes of administration are generally classified by the location at which the substance is applied. Common examples include oral and intravenous administration.

Buccal administration is a topical route of administration by which drugs held or applied in the buccal (/ ˈbʌkəl /) area (in the cheek) diffuse through the oral mucosa (tissues which line the mouth) and enter directly into the bloodstream.