What does intra-arterial injection involve?

Intra-arterial injection specifically involves the injection of medication directly into an artery. This method allows for targeted delivery of drugs to a specific area of the body, thereby enhancing the therapeutic effects while limiting systemic exposure. It is often used in situations where localized treatment is required, such as in some cancer treatments or in procedures that necessitate focused vascular interventions.

The other choices involve different routes of administration. Injecting medication into a vein refers to intravenous injection, which allows for rapid systemic circulation. Injecting into muscle describes intramuscular injection, a method used for vaccines and some medications, facilitating absorption into the bloodstream. Injecting into the skin indicates subcutaneous injection, typically used for medications that are absorbed slowly. Each of these methods serves distinct purposes in medical treatments, but only intra-arterial injection precisely defines the delivery into an artery.