February 17, 2007
Other
Question from Montevideo, Uruguay:
Can you explain the exact meaning of the dawn phenomenon? What are the steps to follow to beat it?
Answer:
The dawn phenomenon is common, usually thought to occur from overnight growth and cortisol hormone production that counteracts insulin effects and is somewhat more common in children and adolescents than adults. But, this is very individualized and somewhat changeable at different times of life. Since one cannot easily and safely block the growth hormone and other hormone production, nor would this be desirable, the best counter-balance for such dawn phenomena is delivering sufficient insulin at the pre-breakfast and post-breakfast blood glucose peaks to balance these overnight hormone effects. Using bedtime rather than suppertime NPH (or Lente) used to be our preference, but now we usually use one of the longer lasting analogs such as glargine (Lantus) or detemir (Levemir) to try to avoid the middle-of-the-night peak and provide better “dawn” coverage. Using an insulin pump would be similarly beneficial and even more specifically fine-tuned since the more exact delivery of basal insulins can be adjusted hour-by-hour for the same “dawn” coverage.
SB