Lauenstein et al. assessed the effect of intravenously administered erythromycin on gastric emptying and subsequent small-bowel filling using three-dimensional (3D) MRI in both healthy subjects and patients with functional dyspepsia [17]. Six healthy volunteers and six patients with symptoms of functional dyspepsia ingested 500 ml of a gadolinium-labeled, fluid meal. In healthy volunteers, gastric volumes decreased significantly more after the administration of erythromycin. In three patients with functional dyspepsia, MRI revealed reduced rates of gastric emptying. The administration of erythromycin resulted in a significantly faster rate of gastric emptying in two of those three patients, indicating the possible therapeutic effect of this drug.