Which method of drug use involves smoking or huffing?

The method of drug use that involves smoking or huffing is classified as inhalation. This route allows substances to be absorbed rapidly into the bloodstream through the lungs, leading to quick onset of effects. When drugs are smoked, they are heated to produce vapor or smoke, which is then inhaled directly into the lungs. Similarly, huffing typically refers to inhaling chemical vapors from substances like aerosol sprays or solvents.

In contrast, the other methods listed, such as intranasal, transdermal, and subcutaneous, involve different routes of administration which do not include the direct act of smoking or huffing. Intranasal administration involves delivering a substance directly into the nasal passages, while transdermal refers to the absorption of substances through the skin (often via patches), and subcutaneous involves injecting substances into the layer of fat just beneath the skin. Each of these methods has its own pharmacokinetic profile and effects, distinct from inhalation, making it clear why inhalation is identified specifically with smoking or huffing.