For the average person, an altitude of 1,200 meters does not cause him or her to have a plateau reaction, but a few people may have a plateau reaction, and if they have a plateau reaction and the symptoms are more serious, they should seek medical attention in a timely manner. Plateau reaction usually occurs at altitudes of more than 3,000 meters above sea level. However, it may also occur at altitudes of less than 3,000 meters. The higher the altitude, the lower the oxygen content in the air, but the relationship is not linear. The oxygen content at 1200 meters above sea level is not particularly different from that in a normal living environment, and normal people’s lungs have a certain amount of reserve to adapt to an environment with a slightly lower oxygen content, so generally speaking, plateau reaction does not occur at an altitude of 1200 meters above sea level. Common symptoms of plateau reaction include headache, dyspnea, palpitations and so on. If your heart and lungs are not functioning well, you may have a plateau reaction at an altitude of 1,200 meters. It is recommended that people with poor cardiorespiratory function should not go to the plateau area at will, and if they have to go, they should ask their doctors in advance and take protective measures.