Pulmonary system

The pulmonary system is the lungs and airways that bring oxygen into the blood and remove carbon dioxide with every breath.

Air passes through the nose and mouth, down the trachea, and into branching bronchi and bronchioles that end in millions of tiny air sacs called alveoli. Gas exchange happens across the alveolar wall, which is thin enough that inhaled substances, including nicotine, cannabinoids and pollutants, can enter the bloodstream within seconds. The lungs are lined with mucus and cilia that trap and sweep out particles, and their immune cells respond quickly to irritants.

Pulmonary health comes up in cannabinoid discussions in two ways: inhalation as a delivery route with fast onset, and the respiratory risks of smoking or vaping any material. Smoke contains tar and combustion by-products regardless of the plant, and inhaled additives have been linked to lung injury. Cannabinoids themselves have been studied in laboratory models of airway inflammation, but that research is preclinical and no cannabinoid has an approved use for any lung condition.