Which of the following is the route of administration for parenteral medications?

The oral route involves the administration of medications through the mouth, where they are absorbed via the gastrointestinal tract. This method is not considered parenteral because it relies on the digestive system, which can alter the drug's efficacy and absorption time.

Inhalation refers to the administration of medications through the respiratory tract, delivering drugs directly to the lungs. While effective for certain treatments, such as asthma or respiratory infections, inhalation is not classified as parenteral, as it does not involve injection.

Installation typically refers to the administration of medications through a specific route, such as eye drops or ear drops. Although it may involve direct application, it does not fall under the category of parenteral administration since it is not an injection.

Transdermal administration involves the application of medications through the skin, allowing for systemic absorption. While effective for certain treatments, it is not classified as parenteral since it does not involve injecting the medication into the body.