background. Diabetic gastroparesis is a comman diabetic autonomic neuropathy and is characterized by epigastric discomfort, abdominal pain, intractable nausea and vomiting and so on. None of various agents hgs been demonstrated the long-term efficacy in patients with diabetic gastroparesis. Recently, it has been reported that Cisapride, a new prokinetic agent, promotes gastric emptying through direct action on myenteric plexus by releasing acetylcholin. Therefore, we evaluated the long-terrn effect of cisapride on gastric emptying of solid meals in patients with symptomatic diabetic gastroparesis. Methods: We conducted a 4-week trial of cisapride (10 mg; t.I.d) in 10 diabetic patients with severe upper gastrointestinal symptoms (symptom score>5) and delayed Gastric emptying in gastric emptying time (GET) scan. The symptom scores were assessed at the entry, mid- period and at the end of the 4-week period. The changes of gastric emptying time were also evaluated before and after trial. We also evaluated gastric emptying time in 10 normal persons and 10 diabetic patients without gastrointestinal symptoms to identify whether delayed gastric emptying is detected in diabetic patients regardless of the presence of symptoms. Results: 1) Nine of 10 diabetic patients with severe symptoms experienced symptomatic improvement and 8 patients of them were improved within 2 weeks after trial of cisapride. 2) Gastric remaining radioactivities at 90 min were significantly decreased in 10 diabetic patients (before treatment 54.1+-1.77%, after treatment 29,5+-2.83%, p<0.05) However, 4 of 10 patients were not improved at the end of 4-week trial and 3 patients of them had severe other autonomic neuropathy. 3) There was no difference in gastric emptying time between normal persons and asypmtotnatic diabetic patients but only one asymptomatic diabetic patient with orthostatic hypotension had delayed gastric empty- ing (T,=100 mm). 4) There was no remarkable side effect during cisa- pride trial. Conclusion: We experienced improvement of symptoms and delayed gastric emptying in diabetic patients with severe gaetroparesis after 4-week trial of cisapride. Most of asymptomatic diabetic pati0nts had no delayed gastric emptying in GET scan.