Hypoglycemia: an overview.

Hypoglycemia was not described as a human clinical syndrome until exogenous insulin was discovered. Much of our current knowledge of the symptoms of hypoglycemia derived from the reactions of schizophrenics to insulin coma therapy in the late 1920's. The diagnosis of hypoglycemia cannot be made simply on the basis of a blood glucose level since many asymptomatic persons have levels below 50 mg/100 ml. The diagnosis should be made only if symptoms occur at the glucose nadir and are relieved by the administration of glucose. The most common organic cause of hypoglycemia is functioning islet-cell tumor. By far the most prevalent type of hypoglycemia is idiopathic (function), a condition whose pathophysiology is not understood and which has given rise to a popular lay "mythology."