The dawn phenomenon, sometimes called the dawn effect, is an early-morning (usually between 2 a.m. and 8 a.m.) increase in blood sugar (glucose) which occurs to some extent in all humans, more relevant to people with diabetes. It is different from chronic Somogyi rebound in that dawn phenomenon is not associated with nocturnal hypoglycemia. It is thought to occur due to temporal elevation in serum cortisol, epinephrine and norepinephrine associated with transition from sleeping to wakefulness.
The dawn phenomenon is a normal physiological response and does not require medication adjustment in most diabetics. In most of the cases, there is no need to change insulin dosing of patients who encounter the dawn phenomenon.
- Rocky Morning Highs?, Diabetes Forecast, September 2008
- "Diabetes Journals - The Dawn Phenomenon". Archived from the original on 2009-04-07. Retrieved 2009-05-01.