During the last years we have employed acid-suppression duodenal diversion procedures (truncal vagotomy-partial gastrectomy plus Roux-en-Y gastrojejunostomy) in addition to antireflux surgery in order to treat all the pathophysiological factors involved in the genesis of Barrett's esophagus. We have observed very good results concerning the clinical and objective control of GERD at the long-term follow up after this procedure. However, it could be associated with other nonesophageal symptoms or side-effects. This study was conducted to evaluate the presence of gastrointestinal symptoms (diarrhea, vomiting, dumping, weight loss and anastomotic ulcers) after this operation. In this prospective study 73 patients were assessed using a careful clinical questionnaire asking regarding these complications at the early (< 6 months) and late (> 6 months) follow-up (average of 32.4 months). In the early postoperative period, diarrhea was present in 64% (19% considered severe 10-90 days after surgery), dumping in 41% and loss of weight in 71% of cases. Diarrhea occurred daily in 47.7% in the early postoperative period, but only in 16% of cases after 1 year. Shortly after surgery, steatorrea was observed in 9% of cases and responded well to medical treatment. Severe diarrhea or dumping was rare (5% of cases). These symptoms improved significantly after 1 year with medical management (45%, 20% and 30%, respectively) and 42% of patients regained their normal body weight. Only two patients presented anastomotic ulcers and were treated satisfactory with proton pump inhibitors. Revisional surgery was indicated in two patients with severe dumping syndrome. Most side-effects identified by this study were mild and diminished 1 year after operation.