The effect of exenatide and erythromycin on postprandial symptoms and their relation to gastric functions.

BACKGROUND: The relationship between abnormal gastric motor function and postprandial abdominal symptoms has not been fully clarified. The aim of the study was to investigate this relationship in response to mediators that affect gastric function. METHODS: Ten healthy volunteers participated in a 3-way cross-over study of treatment with placebo, exenatide and erythromycin. The studies were performed at 1-week intervals. Each subject underwent 3-dimensional single photon emission computed tomography to measure fasting and postprandial gastric volumes. A combined nutrient drink test and cutaneous electrogastrography (EGG) were performed on the next day. RESULTS: Erythromycin reduced postprandial symptoms compared with placebo. The postprandial gastric volume after exenatide was greater than after placebo and erythromycin treatment. Exenatide did not aggravate postprandial symptoms compared with placebo. The ratio of postprandial over fasting gastric volume was inversely correlated with the total postprandial symptom score after placebo, exenatide and erythromycin treatment. The postprandial symptom score of the normal EGG group was significantly lower than that of the abnormal group, considering overall treatments. CONCLUSIONS: Erythromycin reduced postprandial symptoms, whereas exenatide did not aggravate postprandial symptoms, possibly due to its enhancement of gastric accommodation. An abnormal EGG rhythm was associated with postprandial symptoms.