Effect of Intravenous Tolbutamide on Serum Insulin Levels in Pancreatic Diabetes

Intravenous tolbutamide was administered to seven patients with diabetes secondary to chronic calcific pancreatitis who had not previously received insulin. A matched group of normal controls was similarly investigated. The pancreatic diabetic patients were found to respond to tolbutamide with a significantly impaired serum insulin rise compared to the control group, while their fall in plasma glucose was delayed and significantly less pronounced. The relationship between insulin responses in pancreatic and in primary diabetes is briefly discussed and therapeutic implications of the findings are considered.