Precautions before the examination: 1.No smoking one day before the examination 2.Fast food and water before 12:00 p.m. one day before the examination 3.Inform the doctor of your past medical history and drug allergy history 4.Be accompanied by an adult relative or friend on the same day, and remove the removable dentures before the examination Precautions after the examination: 1.A companion is required within 3 hours after the examination 2.No spicy food or alcohol within 8 hours after the examination 3.Do not drive a motor vehicle, operate machinery or engage in high-altitude work within 8 hours after the examination to prevent accidents 4.It is best not to do work requiring actuarial, logical analysis, etc. within 8 hours after the examination.