Which route of drug administration is exemplified by absorption through the lungs, such as with N2O or albuterol?

The correct answer is inhalation, which refers to the administration of drugs that are absorbed through the lungs. This route is particularly effective for certain medications because it allows for rapid absorption directly into the bloodstream via the highly vascularized lung tissue. Drugs like nitrous oxide (N2O) and albuterol are commonly administered this way due to their intended effects that can be achieved quickly. For instance, albuterol is a bronchodilator used to manage asthma and other respiratory conditions; inhalation allows it to directly target the lungs and provide fast relief.

Inhalation offers unique advantages, such as avoiding first-pass metabolism by the liver, which is a key consideration for certain medications. This route can also minimize systemic side effects that might be more pronounced with other forms of administration. Additionally, the inhalation route is often preferred in emergency situations, such as with N2O for sedation, as it allows for rapid action and easy control of dosage.