MODEL RELEASED. Oxygen therapy. Man sits at home and breathes oxygen through a tube to the nose. Beside him is oxygen administering equipment. Oxygen therapy supplies oxygen-enriched air to patients who have symptoms of hypoxia (inadequate oxygen in the body tissues). It is usually administered due to lung and breathing disorders, such as occur in asthma, chronic bronchitis and emphysema. Home therapy (as seen here) is usually provided for cases of severe asthma.