What type of administration route is generally used for rectal suppositories?

The administration route used for rectal suppositories is rectal because these medications are specifically designed to be inserted into the rectum where they dissolve and are absorbed into the bloodstream or exert their effects locally. This method is beneficial for patients who may have difficulty swallowing medications, are vomiting, or when other routes of administration are not viable. Rectal administration allows for relatively quick systemic absorption, making it effective for certain conditions and providing a non-invasive option for medication delivery.

The other options represent different routes of administration: intravenous involves delivering medication directly into the bloodstream, intramuscular involves injecting medication into muscle tissue, and transdermal involves applying medication through the skin for systemic absorption. Each of these routes has its specific use cases, but they do not pertain to rectal suppositories.