THE STIMULATORY EFFECT ON INSULIN SECRETION IN LONG-TERM TOLBUTAMIDE TREATMENT

Abstract

ABSTRACT Previous studies of the long-term effect of sulphonylurea have consistently failed to reveal any chronic stimulation of insulin secretion. This failure is probably due to the inadequate design used. In the present study an unquestionable long-term action of tolbutamide on the beta-cell has been demonstrated. We have studied diabetic patients treated for several years during the days just before and just after experimental withdrawal of the drug and have ascertained by this means that the blood sugar is almost unchanged. It has been found that the urinary insulin excretion decreased significantly after withdrawal of tolbutamide. It is concluded that the long-term clinical effect of tolbutamide is at least partly due to a stimulatory action of tolbutamide on the beta-cell.