Patients with mild carbon monoxide poisoning are usually in a clear state of mind. If they are removed from the poisoned environment and given fresh air or a certain concentration of oxygen to inhale, the symptoms usually disappear completely in a few hours to a few days. Carbon monoxide poisoning is mainly caused by the combination of carbon monoxide and hemoglobin in the blood to form carboxyhemoglobin, resulting in a decrease in the oxygen-carrying capacity of hemoglobin, thus causing damage to human tissue cells. In mild carbon monoxide poisoning, the concentration of carboxyhemoglobin in the blood will be less than 30%, and the patient will have headache, dizziness, palpitations, nausea, fatigue, vomiting, abdominal distension, weakness of the limbs, and even transient fainting. The symptoms of dizziness and headache may disappear after carbon monoxide poisoning is relieved, leaving no after-effects. It is recommended to evacuate the patient quickly from the poisoned environment, breathe fresh air and open the window to ventilate, most of the patients wake up in time and get better, and can recover within a few days, such as the patient has been to the doctor, give oxygen inhalation can quickly relieve the symptoms.