Dawn phenomenon

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) relevant to people with diabetes. It is different from chronic Somogyi rebound in that dawn phenomenon is not associated with nocturnal hypoglycemia.

The dawn phenomenon can be managed in many patients by avoiding carbohydrate intake at bedtime, adjusting the dosage of medication or insulin, switching to a different medication, or by using an insulin pump to administer extra insulin during early-morning hours. In most of the cases, there is no need to change insulin dosing of patients who encounter the dawn phenomenon.

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