Controlled extension of oral antidiabetic therapy on former insulin dependent diabetics by means of the combined i.v. glibenclamide-glucose-response-test

Summary A new sulphonylurea response test is described for predicting the results of long-term treatment with a recently developed sulphonylurea compound, glibenclamide, particularly in insulin-dependent tolbutamide-non-responsive elderly diabetics. The test is based on the observation that the insulin-stimulating capacity of glucose and the determination of the insulin increases are strikingly potentiated following glibenclamide plus glucose i.v. (25 plus 0.33 g/kg body weight) in serum samples where insulin binding antibodies have been removed. 11 out of 40 diabetics demonstrating between 60 and 90 min following injection, a mean increase of insulin of more than 500 per cent above the initial values, correlated satisfactorily with successful long-term oral treatment with glibenclamide. A positive glibenclamide-glucose-response test contrasted with primary failure of glibenclamide therapy in only one patient suffering from haemochromatosis. Oral treatment with glibenclamide may have certain advantages over insulin therapy, especially in elderly diabetics suffering from visual impairment, who are unable to inject themselves with insulin.Support of this Study by Deutsche Forschungsge-meinschaft (Pf 38/28) is gratefully acknowledged.