The clinical picture of insulin shock from overdosage (hyperinsulinism) has become quite generally known. Hypoglycemia in diabetes from continued daily overdosage of insulin is described by John.1There have been described by Harris,2Pribram3and Cammidge4a variety of clinical syndromes in which there is an associated spontaneous hypoglycemia. This has been considered to result from hyperinsulinism, although failure of hepatic glycogenolysis is also a hypothetic cause for hypoglycemia. Hyperinsulinism as a physiologic abnormality is a logical corollary to the fact that insulin, the active hormone which stimulates the oxidation of carbohydrates, is diminished in diabetes. The analogy to the known plus and minus quantitative alterations of other endocrine secretions is exact. Although adenomas of island tissue have been found at autopsy, and in some instances in which the clinical observations included a hypoglycemia, it was not until quite recently that any hypoglycemic state was definitely