Drugs given enterally are absorbed more rapidly and completely than those given intravenously.

• A. True
• B. False
• C. Cannot be determined from the statement
• D. Only in animals

Answer: (B)

The main idea is how the route of administration shapes how much of a drug reaches the bloodstream and how quickly it does so. Intravenous delivery puts the drug directly into systemic circulation, giving almost immediate and complete availability (100% bioavailability) with the fastest possible onset. When drugs are given enterally (through the GI tract, such as by mouth), they must dissolve, pass through the intestinal wall, and often survive first-pass metabolism in the liver before reaching the bloodstream. This process can be slow, variable, and incomplete, because factors like gastric emptying, intestinal transit time, drug solubility, pH, enzymatic degradation, and liver metabolism all influence how much drug actually gets into circulation.

Because of these factors, enteral absorption is typically slower and less complete than intravenous absorption. In animals, additional species-specific differences in GI physiology can further affect this, making IV administration consistently more reliable for rapid and predictable systemic exposure. So the statement that enteral administration is absorbed more rapidly and completely than intravenous is not accurate.