A
route of administration in
pharmacology and
toxicology is the path 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. Routes can also be classified based on where the target of action is. Action may be topical (local), enteral (system-wide effect, but delivered through the
gastrointestinal tract), or parenteral (systemic action, but delivered by routes other than the GI tract).