The aim of the study was to use a novel combination of two methods for the simultaneous evaluation of two effects of oral cisapride in 10 diabetic patients with autonomic neuropathy; gastric empyting time was measured by following radio-opaque markers and orocaecal transit time by the sulphasalazine-sulphapridine method. The study was of double-blind, randomized, placebo-controlled, cross-over design. It was possible to evaluate the effect of a prokinetic drug on gastric emptying and orocaecal transit times using these two noninvasive techniques at the same time. Cisapride significantly reduced both the gastric empyting (1.2 h versus 2.1 h) and orocaecal tansit (5.9 h versus 7.7 h) times.