A study of the sensitivity to a test dose of exogenous insulin was undertaken in eight patients with primary and five with secondary (Sheehan's syndrome) adrenal insufficiency. The great majority showed hypersensitivity to insulin and hypoglycemia-unresponsiveness was present in all.

The hypersensitivity was primarily the result of excessive peripheral insulin action as shown by the increased disappearance rate (k) of an intravenous glucose load, in the well nourished patient.

A possible failure in glycogenesis and consequent reduced glucose release by the liver, which might explain the hypoglycemia-unresponsiveness, was not confirmed by the glucagon test, suggesting that if there is liver impairment it is in its rate of glucose release independent of the amount of glycogen present and related to the glucocorticoid influence on the threshold of blood glucose regulation by the liver.