The Somogyi effect, also known as chronic Somogyi rebound, is the body's tendency to respond to low blood sugar by producing high blood sugar. These conditions are clinically referred to as hypoglycemia and hyperglycemia, respectively. The Somogyi effect is named after a Hungarian-born researcher who worked in the United States as a biochemistry professor at Washington University and a clinical chemist at the Jewish Hospital, both in St. Louis, Missouri.
Michael Somogyi is credited with preparing the first insulin treatment for children with diabetes. This is a medical condition characterized by high blood sugar as a result of the insufficiency of the hormone insulin, or a lack of cell response to it. After this achievement, made in 1922, Somogyi plunged himself into the study of this disease. In 1938, he revealed his findings—that insulin treatment might actually make diabetes unstable.
In the Somogyi effect, the body responds to the drop in its blood glucose levels by producing counterregulatory hormones that include epinephrine and glucagon. As opposed to insulin, which lowers blood glucose, these hormones raise it by using the molecule glycogen, which is produced by the liver, to transform into glucose. This process then induces hyperglycemia, or high blood sugar.
The Somogyi effect is comparable to the dawn effect, also known as the dawn phenomenon, in that the patient affected with either condition wakes up with high blood sugar. The dawn effect can actually take place anytime between 2 a.m. and 8 a.m. By contrast, the Somogyi effect is usually associated with the nighttime.
There is only one way to prevent the chronic Somogyi rebound: avoid low blood sugar levels. This can be done by testing blood sugar up to 10 times a day. When the Somogyi rebound takes place, however, symptoms such as night sweats and accelerated heart rate occur.
At the beginning of the 21st century, some researchers in the medical community developed doubts that threatened the validity of the Somogyi effect. Chief among such doubts is the level of importance of counterregulatory hormones in causing high sugar levels. For instance, some people with diabetes, particularly those with the type 1 strain, do not wake up due to the hormone epinephrine failing to release. Additionally, some studies indicate that a high blood glucose level in the morning does not necessarily follow a low blood glucose level in the nighttime.