Intraosseous (IO) injection delivers medication to which site?

Intraosseous (IO) injection delivers medication to which site?

• A. Bone marrow cavity
• B. Vein
• C. Muscle
• D. Subcutaneous tissue

Answer: (A)

Intraosseous delivery places medications into the bone marrow cavity, the medullary space inside a bone. This space is highly vascular, with networks of blood vessels that allow drugs to quickly enter the systemic circulation through the marrow’s venous sinusoids. That rapid entry into the bloodstream is why this route is used when IV access is difficult, giving a fast, nearly IV-like onset. Think of it this way: it’s not going into a vein directly, nor into muscle or under the skin. It’s placed in the hollow bone interior, where the drug rapidly drains into the circulation.

Intraosseous delivery places medications into the bone marrow cavity, the medullary space inside a bone. This space is highly vascular, with networks of blood vessels that allow drugs to quickly enter the systemic circulation through the marrow’s venous sinusoids. That rapid entry into the bloodstream is why this route is used when IV access is difficult, giving a fast, nearly IV-like onset.

Think of it this way: it’s not going into a vein directly, nor into muscle or under the skin. It’s placed in the hollow bone interior, where the drug rapidly drains into the circulation.