Route of Administration – Definition

route of administration of drug

Route of Administration – the method by which a person takes or receives a drug. The common routes administration are oral (by mouth), sublingual (beneath the tongue), injection, topical, transdermal, and rectal.

Women may use some drugs intravaginally. Some drugs are available only in certain forms, such as injectable.

Many drugs are available in numerous forms. Factors that influence the selected route of administration include the drug’s formulation and the person’s ability to take or receive a particular form of the drug. For example, a young child or person who has difficulty swallowing or is experiencing nausea and vomiting may better handle a drug administered by transdermal patch, injection, or rectal suppository. Injection allows the most rapid delivery; other forms allow slower entry of the drug into the blood circulation.

RouteFormsEntry Mechanism
injectionintravenous (IV), intramuscular (IM), subcutaneous (SC)IV: into a vein, direct entry to the blood circulation
IM: into a muscle; rapid absorption into the blood circulation
SC: into the fatty tissue beneath the skin; slow absorption into the blood circulation
oral (per os or PO)tablet, capsule, liquiddigestion breaks down the product, with absorption usually in the small intestine
rectalsuppositorySoft carrier wax melts, drug becomes absorbed into the blood circulation through the wall of the rectum
sublingual (SL)tablet, liquiddissolves under the tongue, becoming absorbed into the blood circulation through the mucosa of the mouth
topicalcream, ointment, gel, lotion, sprayintended to remain within the layers of the skin
transdermalpatch, cream, ointmentintended to be absorbed through the skin into the blood circulation


How did you like this article?

Page last reviewed:

About Us