Which medication administration route involves piercing the skin?

Injection administration is the route that involves piercing the skin to deliver medication directly into the body. This method allows for the rapid absorption of the drug into the bloodstream or the target area, making it effective for various types of medications, including vaccines, insulin, and other treatments that require precise dosing or faster action than other routes.

Other routes, such as inhalation, rectal, and oral administration, do not involve breaking the skin. Inhalation delivers medication through the respiratory system, rectal administration involves placing medication into the rectum, and oral administration requires swallowing medication that then passes through the digestive system before entering the bloodstream. Therefore, the unique characteristic of injection administration is its direct method of using a needle to penetrate the skin, allowing for immediate and effective delivery of medication.