Oxygen intake can relieve diseases and symptoms caused by hypoxia, but excessive oxygen intake can cause varying degrees of airway dryness and damage to the mucous membranes of the respiratory tract. 1. Benefits of Oxygen Inhalation (1) Oxygen inhalation in patients in the acute stage of heart attack can increase the amount of oxygen supplied to the myocardium by the coronary artery, improve the myocardial hypoxia condition of the patients, and can prevent or reduce the frequency of angina pectoris. (2) Oxygen inhalation in asthma patients can increase the concentration of oxygen in the bronchial tubes, which is conducive to the control of asthma. (3) Long-term oxygen therapy for patients with chronic obstructive pulmonary disease can improve blood oxygen levels, relieve patients’ symptoms of hypoxia, improve patients’ exercise tolerance and mental status, and improve lung function. (4) Oxygen inhalation for carbon monoxide poisoning can rapidly correct the patient’s hypoxia, accelerate the dissociation of carboxyhemoglobin and increase the discharge of carbon monoxide. 2. Side effects of oxygen inhalation (1) Inhaled oxygen is usually dry, which may lead to different degrees of airway dryness and respiratory mucosa damage. (2) Excessive inhalation of oxygen may produce oxygen toxicity. The time and concentration of inhaled oxygen should be closely controlled to avoid excessive inhalation of oxygen. Oxygen therapy is commonly used as an adjunctive treatment and is usually safer, but to prevent accidents, it is recommended that oxygen therapy be administered under medical supervision.