OBJECTIVES: To investigate protective effect of rebamipide against nonsteroidal anti-inflammatory drugs (NSAIDs)induced gastroduodenal mucosal injury. METHODS: Randomized eight patients with rheumatic disease starting NSAIDs underwent pre-treatment gastroduodenoscopy,and degree of mucosal injury and several gastrointestinal (GI)symptoms were graded by Lanza score scale (rating from 0 to 4)and symptom score scale (rating from 0 to 3).Eight weeks after the subjects had received concomitant rebamipide 100mg bid and NSAIDs they underwent post-treatment gastroduodenoscopy and degree of mucosal injury and GI symptoms were graded.Randomized previous NSAIDs-used 20 patients with rheumatic disease were also investigated.Eight weeks after 100mg bid with concomitant NSAIDs,they underwent gastroduodenoscopy and degree of mucosal injury and GI symptoms were graded. RESULTS: All eight patients who received concomitant rebamipide and NSAIDs had no interval changes between pre and post-treatment mucosal injury scores and had little interval changes between pre and post-treatment symptom scores. In previous NSAIDs-used patients with rheumatic disease,incidence of each gastric ulcer and duodenal ulcer were 16.7%and 11.1%and all mean symptom scores were lower than 1.0.No special adverse effect was developed during the study. CONCLUSION: Rebamipide seems to have a good protective effect against NSAIDs induced mucosal injury and GI symptoms and probably have rare adverse effect.