Which route is administered under the skin?

• A. Subcutaneous
• B. Intravenous
• C. Intramuscular
• D. Topical

Answer: (A)

Delivering medication under the skin means placing it into the subcutaneous tissue, the fatty layer just beneath the skin. This route is chosen when a slower, steadier absorption is desired, or when the medication should be absorbed gradually rather than immediately. The subcutaneous tissue has fewer blood vessels than muscle, so absorption into the bloodstream happens more slowly, often giving a longer or smoother effect. This contrasts with intravenous administration, which dumps the drug directly into the bloodstream for rapid action; intramuscular administration, which goes into muscle tissue with more blood flow and usually faster absorption than subcutaneous; and topical administration, which is applied on the skin surface for local effect rather than systemic absorption. Examples commonly given subcutaneously include insulin and some anticoagulants like heparin, while topical forms act locally on the skin.