Which method of administration is applied to the surface of the skin?

The method of administration that is applied to the surface of the skin is topical. Topical administration involves the application of a medication directly onto the skin or mucous membranes for localized effect. This method allows the active ingredients to absorb into the skin to treat conditions such as rashes, inflammation, or pain in a specific area.

Other methods of administration, such as oral, intravenous, and intrathecal, are different in nature. For example, oral administration involves taking medication by mouth, which then enters the gastrointestinal tract for systemic absorption. Intravenous administration delivers medication directly into the bloodstream, providing rapid effect but not localized treatment. Intrathecal administration involves injecting medication into the spinal canal, targeting the central nervous system. Each of these methods serves distinct clinical purposes, but topical administration is specifically characterized by its application directly onto the skin's surface.