Which administration route involves drugs bypassing the GI tract entirely?

The administration route that involves drugs bypassing the gastrointestinal (GI) tract entirely is parenteral administration. This method typically includes administering medications through injections, which can be intravenous, intramuscular, or subcutaneous. By using this route, the drug is delivered directly into the bloodstream or tissue, thus avoiding the absorption barriers present in the GI tract, such as digestive enzymes, stomach acidity, and potential first-pass metabolism in the liver. This route allows for rapid onset of action and is particularly useful for patients who may be unable to take medications orally due to factors like vomiting or unconsciousness.

Other routes such as enteral and oral administration involve the GI tract, with enteral administration specifically referring to medications that are absorbed via the digestive system, typically via the mouth or feeding tubes. Topical administration involves applying a drug to the skin or mucous membranes for localized effect, which also does not bypass the GI tract in the way parenteral administration does.