In what context is "intra-arterial" drug delivery typically used?

Intra-arterial drug delivery is typically used for its ability to achieve localized or systemic effects. This method involves injecting medication directly into an artery, which allows for precise targeting of a specific area in the body. This can be particularly advantageous in cases where high concentrations of a drug are needed in a localized region, such as tumors, without exposing the entire body to potential side effects.

When drugs are delivered intra-arterially, they can be efficiently distributed to tissues that have a direct blood supply through that artery. For example, in cancer treatment, delivering chemotherapy directly into the blood supply of a tumor can maximize the drug's efficacy while minimizing systemic toxicity.

This mode of drug delivery is not typically associated with mild pain relief, as it is more complex and requires specialized techniques. Furthermore, it is considered invasive rather than non-invasive, as it involves accessing the vascular system. Lastly, routine immunizations are generally administered via intramuscular or subcutaneous routes rather than intra-arterially, making that context unsuitable for this method of delivery.