What does the term "subcutaneous" refer to in medication administration?

The term "subcutaneous" specifically refers to a route of medication administration where the drug is injected into the tissue layer between the skin and the muscle. This method allows for the medication to be absorbed more slowly compared to other routes, such as intravenous or intramuscular, making it useful for certain types of medications that require a gradual release into the bloodstream.

In the context of pharmacology, subcutaneous injections are commonly used for administering medications such as insulin or certain vaccines, where a slower and steady absorption rate is beneficial. This route of administration is typically preferred for patients who require self-injection, as it is relatively easy to perform and can often be done at home.

The other options refer to different routes of administration that involve different methods and physiological absorption processes, thus confirming that the term "subcutaneous" specifically denotes injections administered under the skin.