ABSTRACT
[Summary] Thedawn phenomenon is a term used to describe hyperglycemia or an increase in the amount of insulin needed to maintain normoglycemia, occurring in the absence of antecedent hypoglycemia, during the early morning hours, and mostly affecting children with type 1 diabetes. Currently, hyperglycemia before breakfast time is defined as dawn phenomenon, and postbreakfast abnormal hyperglycemia is referred as the extended dawn phenomenon. Dawn phenomenon is regarded as the result of the β cell dysfunction, which increased endogenous glucose production and the persistent insulin resistance. By using continuous glucose monitoring technology, dawn phenomenon can be effectively identified:The difference between the lowest glucose level during nocturnal time and the glucose value before breakfast over 1. 11 mmol/L. And the long-acting insulin analogs and insulin pump are effective treatments for dawn phenomenon.