What route of administration is characterized by drugs being swallowed and absorbed in the small intestines?

The route of administration characterized by drugs being swallowed and absorbed in the small intestines is oral. When a drug is taken orally, it passes through the gastrointestinal tract, where it is broken down by gastric juices and enzymes. The active ingredients are then absorbed primarily in the small intestine due to its large surface area and rich blood supply.

This method of administration is highly convenient and is the most commonly used route for many medications. Once absorbed, the drugs enter the bloodstream and can exert their effects throughout the body.

Other routes, such as sublingual and rectal, involve different physiological processes and locations for absorption, while parenteral refers to any route that bypasses the gastrointestinal tract, often involving injections. Hence, the oral route is distinct in its reliance on the digestive system for both absorption and bioavailability of drugs.