The effect of erythromycin on gastric emptying is modified by physiological changes in the blood glucose concentration.

Abstract

The aim of this study was to determine whether variations in the blood glucose concentration within the normal postprandial range affect the gastrokinetic action of erythromycin. Six healthy male volunteers, aged 20-33 yr underwent measurements of gastric emptying on 2 separate days; blood glucose concentrations were maintained at approximately 4 mmol/L (72 mg/dl) on 1 day and at 8 mmol/L (144 mg/dl) on the other. The order of the two studies was randomized and they were separated by 4-7 days. On both days, erythromycin (3 mg/kg) was administered intravenously over 15 min immediately before consumption of 300 g minced beef labeled with 20 MBq 99mTc-sulphur colloid chicken liver and 150 ml water labeled with 67Ga-EDTA. Gastric emptying of solid (p < 0.05) and liquid (p < 0.0001) were slower at a blood glucose concentration of 8 mmol/L (144 mg/dl) when compared to 4 mmol/L (72 mg/dl). The slowing of gastric emptying was associated with greater retention of both solid and liquid in the proximal (p < 0.06) and distal (p < 0.01) stomach. After administration of erythromycin, gastric emptying and intragastric distribution of solids and liquids is influenced by physiological changes in the blood glucose concentration.