Hypoglycemia

Alternative names:

insulin shock; low blood sugar

Definition:

Hypoglycemia is a condition of abnormally low blood sugar (glucose). Insulin shock is a term for extensive hypoglycemia that results in unconsciousness.

Causes, incidence, and risk factors:

Hypoglycemia results when glucose is used up too rapidly, when glucose is released into the bloodstream more slowly than is needed by the body, or when excessive insulin (a hormone secreted by the pancreas in response to increased glucose levels in the blood) is released into the bloodstream.

Hypoglycemia is relatively common in diabetics. It occurs when too much insulin or oral antidiabetic medication is taken, not enough food is eaten, or from a sudden increase in the amount of exercise without increasing the intake of food.

Relative hypoglycemia is a fairly common occurrence in the newborn. Significant hypoglycemia may occur in a newborn infant from a gestational diabetic or a diabetic mother (called an IDM for "infant of diabetic mother"). If the mother's blood sugar was persistently high, the infant's pancreas assisted in controlling the excess blood sugar by secreting extra insulin. When the infant is born, that maternal blood sugar is no longer available and the increased insulin drives the infant's blood sugar down to dangerous levels. This is a medical emergency that may result in seizures and neurological damage if not treated.

Hypoglycemia can occur as an idiopathic (without known cause) condition. In this case, people who are not diabetic and who do not have other known causes of hypoglycemia experience symptoms of the disorder.

Hypoglycemia can occur because of an insulin-secreting tumor of the pancreas, liver disease, or as a response to the ingestion of alcohol. Hypoglycemia occurs in adults, infants, and children. The incidence is approximately 1 out of 1000 people.