From Bay City, Michigan, USA: My friend's eight year old
daughter old has type 1 diabetes, and she was wondering what the
differences are between rebound and the dawn phenomenon. What
test could be done to determine what her daughter has? The dawn
phenomenon is a sudden rise in blood sugar level during the
early morning hours (3:00-7:00 am generally). This condition
occurs more often in people with insulin-treated diabetes and
sometimes, but of a lesser degree, in patients with non-insulin
treated diabetes. Unlike the Somogyi Effect (rebound), it is not
a result of an insulin reaction, but it is believed to be due to
a waning of the insulin action associated with a surge in the
stress hormones (growth hormone and cortisol) over the last part
of the night. People who have high levels of blood glucose in
the morning before eating may need to monitor their blood sugar
during the night, and, if sugar levels are rising, adjustments
in the evening snacks or insulin dosage may be recommended.
Rebound hyperglycemia i