Which route of drug administration is used to deliver medication directly into the bloodstream?

The route of drug administration that delivers medication directly into the bloodstream is the sublingual route. When medication is placed under the tongue, it rapidly dissolves and is absorbed through the mucous membranes directly into the bloodstream. This method provides a quick onset of action because it bypasses the digestive system and first-pass metabolism in the liver, allowing for more immediate effects.

In contrast, oral administration involves swallowing medication, which must first pass through the digestive tract before entering the bloodstream. Inhalation is used for delivering medications to the lungs and may not enter the systemic circulation as swiftly as sublingual. The rectal route is another alternative that can provide systemic effects but is generally less favored than sublingual for immediate delivery because absorption can vary significantly.