Surface anesthesia, also known as superficial anesthesia, is administered by spraying or applying anesthetics directly to the mucosal surface to make the mucosal surface painless and tingly, which is mainly used to make the mucosa anesthetized. Surface anesthesia is performed first to prevent the patient from feeling obvious pain when piercing the mucosa and to reduce the patient’s fear, so that the patient can better cooperate during surgery or tooth extraction. If the patient has inflammation of the pharynx, some patients may feel nauseous when local anesthesia is administered.