The dawn phenomenon refers to periodic episodes of hyperglycemia occurring in the early morning.
Mechanism: increase in gluconeogensis by the liver with an inadequate insulin response
Patient selection: type 1 and type 2 diabetes
Clinical features:
(1) elevations in blood glucose levels in the morning
(2) the hyperglycemia may be difficult to control
Exclusions:
(1) not explained by food intake
(2) not related to the Somogyi effect or nocturnal hypoglycemic events
(3) not explained by poor effort at glycemic control
It is more likely to be detected in a person with continuous or frequent glucose monitoring.