route of administration /ro̅o̅t, rout/ [Fr, route, course; L, administrare, to serve] , (of a drug) any one of the body systems in which a drug may be administered, such as intradermally, intrathecally, intramuscularly, intranasally, intravenously, orally, rectally, subcutaneously, sublingually, topically, or vaginally. Some medications can be given by only one route because absorption or maximum effectiveness occurs by that route only or because the specific substance is toxic or damaging when given by another route.
