Hypothalamic--pituitary function in depressive illness: insensitivity to hylycaemia.

The insulin tolerance test was performed in 16 severely depressed patients on admission to hospital and after treatment with electric convulsion therapy. The mean plasma cortisol response to hypoglycaemia was significantly impaired before treatment, particularly in the patients who also showed resistance to dexamethasone suppression. The results are consistent with hypothalamic-pituitary insensitivity to hypoglycaemia in these subjects.