Controlled oxygen therapy for the treatment of stable dyspnea is an effective prescription medication for treatment of hypoxemia. Oxygen prescriptions (duration and flow) should be based on arterial blood gas measurements and 6 minute walk tests results [80]. Longer term exposure to oxygen therapy (> 15 hr/day) over a number of years significantly improves survival [81, 82]. Although oxygen therapy prescription during exercise is not well supported by evidence, in current practice, oxygen during exercise is being prescribed for individuals with severe COPD who become hypoxemic only when exercising. Oxygen treatment during exercise facilitates rehabilitation and permits increased activity by decreasing ventilatory requirements and thereby reducing the work of breathing. While there is no concrete evidence for the benefits of using oxygen therapy in treatment of palliative end-stage dyspnea [83], oxygen therapy is conventionally used as a comfort measure, best delivered by nasal cannula up to 4-5L/min [84].