If you inhale toxic gas, you should first leave the poisoned environment quickly and then inhale fresh air or oxygen. Generally, if the poisoning is mild, there is only a slight dizziness, cough and throat discomfort, and the symptoms will be relieved soon after leaving the poisoned environment. If the amount of poisonous gas inhaled is relatively large, there will be obvious physical symptoms, including violent coughing, spasm of the airway, difficulty breathing, sputum, and even acute bronchitis, acute aspiration pneumonia and other symptoms, and even suffocation. In these cases, it is necessary to go to the hospital quickly for emergency treatment, which can be given to relieve airway spasm. In addition to oxygen inhalation, nebulized inhalation is also required, which can be combined with corticosteroids and bronchodilators. In addition, intravenous medications to relieve airway spasm, such as theophylline and intravenous hormones, can be applied. In addition, symptomatic supportive treatment can be given according to the patient’s symptoms of toxicity.