Which method of administration allows medication to be absorbed rapidly through the lungs?

Inhalation is the method of administration that allows medication to be absorbed rapidly through the lungs. This route bypasses the digestive system and enters the bloodstream directly through the alveoli in the lungs. The vast surface area of the lungs facilitates this rapid absorption, making inhalation particularly effective for certain medications, such as bronchodilators and anesthetics.

In contrast, intradermal, subcutaneous, and rectal routes of administration involve different absorption mechanisms that generally result in slower onset of action compared to inhalation. Intradermal and subcutaneous routes require the drug to diffuse through skin or subcutaneous tissue, which takes more time to reach systemic circulation. The rectal route can also be variable in absorption due to the presence of blood flow and contents in the intestines. Therefore, inhalation is the superior choice for rapid delivery of medication.