It is nocturnal glycemia caused by decreased effectiveness of insulin and overnight growth hormone release. Therefore, it causes early morning hyperglycemia.
Treat it by moving night-time insulin dose as close as possible to bedtime.
Nocturnal glycemia: It is normal but due to decreased insulin and increased GH release, early morning hyperglycemia occurs.
How to diagnose whether the early morning hyperglycemia in patient is due to Dawn Phenomenon or Somogyi Effect?
Debate regarding Somogyi credibility continues whether Somogyi effect to hypoglycemia is due to nocturnal hypoglycemia or not. In fact, hyperglycemia due to Somogyi effect can actually be due to an insulin-induced insulin resistance1.
1. Shanik MH, Xu Y, Skrha J, et al. Insulin resistance and hyperinsulinemia: is hyperinsulinemia the cart or the horse?. Diabetes Care. Feb 2008;31 Suppl 2:S262-8.