Studies on the pathogenesis of reactive hypoglycemia: role of insulin and glucagon

Fifty-eight patients with biochemical reactive hypoglycemia (blood glucose 45 mg% or less after a 100 g OGTT) were tested, of whom 11 subjects were obese with normal glucose tolerance, 9 were obese with chemical diabetes, 9 had chemical diabetes without obesity, 6 had undergone gastrectomy, 7 had renal glycosuria and 16 were apparently isolated. An exaggerated insulin response to oral glucose was associated with reactive hypoglycemia in the post-gastrectomy syndrome, in normal-weight patients with chemical diabetes and 44% of the patients with the isolated syndrome. In contrast, plasma-insulin values cannot account for the reactive hypoglycemia observed in obese patients (with or without chemical diabetes), in subjects with renal glycosuira and in 56% of the patients with the isolated syndrome. A study of pancreatic-glucagon secretion in a group of twelve subjects with "isolated normoinsulinemic reactive hypoglycemia" failed to demonstrate any significant abnormality in the secretion of this hormone during oral glucose tolerance test or intravenous insulin tolerance test. As suggested by Permutt et al. (1973) biguanide therapy may be useful in the treatment of patients presenting severe and symptomatic reactive hypoglycemia which does not respond to classical dietary management.