[Comparative study of i.v. administration of xylitol and sorbitol to diabetics]

The aim of this study was to investigate the effects of the intravenous administration of xylitol and sorbitol respectively on plasma insulin and blood glucose in subjects with non-insulin requiring maturity-onset diabetes after an overnight fast. All participants had two intravenous applications with an interval of at least 3 days. Part of the patients started with xylitol and had later on sorbitol; the other part had the reversed sequence. There are two series: Series A: Rapid i.v. application of 0.5 g/kg within 10 minutes (n = 8. Series B: i.v. infusion with 0.5 g/kg/hour for 2 hours (n =9). In addition, 4 subjects of this series had another xylitol infusion after pretreatment with tolbutamide (1000 mg orally 60 minutes before starting the infusion). In respect to insulin secretion there were differences between the two compounds related to the speed of application. With the rapid intravenous injection there was a higher peak and a larger total insulin secretion with sorbitol whereas with the infusion insulin secretion was more pronounced with xylitol. Intravenous application of both carbohydrates caused a certain increase in blood glucose. By pretreatment with tolbutamide the increase of blood glucose due to xylitol could be avoided in spite of the fact that the insulin secretion remained unchanged.