Glucose and insulin secretory response patterns following diet and tolazamide therapy in diabetes

Glucose and insulin secretory response patterns during glucose tolerance tests were determined in 28 maturity-onset diabetics, and the sequential effects of diet and a sulphonylurea, tolazamide, were assessed. Untreated diabetics showed hyperglycaemia, increased serum immunoreactive insulin response patterns, delayed insulin release, and relative insulin deficiency. Diet alone partially corrected the hyperglycaemia and serum immunoreactive insulin response but had no effect on the delayed insulin release or relative insulin deficiency. Tolazamide plus diet restored all values towards normal. The net effect of maintenance tolazamide therapy was to (1) restore the insulin secretory response pattern to normal, (2) reduce total pancreatic insulin output, and (3) improve the efficiency of insulin secretion. The results suggest that there is a rational basis for the use of sulphonylurea in all maturity-onset diabetics, including patients with mild carbohydrate intolerance and those who are apparently controlled by diet alone.