The effect of cisapride, 10 mg three times daily, was evaluated in a double-blind randomized study in 118 patients with non-ulcer dyspepsia. Peptic ulcer disease was excluded by endoscopy, gallstones by ultrasonography, and chronic pancreatitis by a series of non-invasive tests. Symptomatic improvement was evaluated by interview after 2 and 4 weeks; the patients also kept a diary. Cisapride caused significant improvement compared with placebo with regard to frequency and severity of symptoms and may therefore be useful in the therapy of non-ulcer dyspepsia.