What is the Somogyi Effect?

Glucagon and insulin are released by the pancreas. Glucagon and insulin have opposite effects: insulin makes the blood sugar go down and glucagon causes blood sugar to go up. They work together to balance blood glucose levels. Glucagon can increase blood glucose levels by causing the liver to release its stored glucose to the blood stream. Insulin lowers blood glucose by allowing tissues to use or store glucose.

When too much insulin is given the blood glucose drops rapidly and hypoglycemia (low blood sugar) results. This can trigger the body to release glucagon (and other hormones) and the result is that glucose is dumped into the blood. This can lead to hyperglycemia (high blood sugar). So, you have hyperglycemia induced by hypoglycemia, or the Somogyi effect. (Somogyi was a scientist who did research on glucose production by liver during times of stress.)

The method of determining if Somogyi effect is occurring is to do a blood glucose curve. Your cat will have a specific pattern of hyperglycemia if the Somogyi effect is occurring. Although at first it seems odd, the treatment for this type of hyperglycemia is to DEcrease the insulin dose. This prevents the hypoglycemia from occurring and triggering the Somogyi effect.