As a highly selective α2adrenergic receptor agonist, Dex has been widely used for analgesia and sedation in children. Dex is administered to enhance the analgesic effect and relieve emergence agitation in children. Dex provides sedation that parallels natural sleep with minimal respiratory depression, which is one of its most attractive properties. Moreover, studies have shown that Dex has an organ protective effect in animals and humans, which promotes its application in pediatric anesthesia. Currently, regardless of the administration route or dose, the use of Dex in children is offlabel. Many studies have shown that there are no severe adverse effects associated with Dex. However, anesthesiologists are still concerned about the adverse effects on the cardiovascular system, especially bradycardia. The reasonable dose and concentration are the key factors for clinical security. 