The efficacy and safety of a combination of buzepide metiodide and haloperidol was assessed in a placebo-controlled double-blind trial during 2 months in 224 patients (154 women, 79 men) with the irritable bowel syndrome. The 2 groups were comparable at inclusion. The efficacy was assessed at days 15, 30 and 60. Inclusion and assessment criteria were clinical, abdominal pain being considered as the main assessment criterion. The combination proved statistically better than placebo on the frequency of symptoms at all visits and on the intensity of the most frequent symptoms (abdominal pain and distension) at the final visit. A previously defined global assessment score was found significantly better in favor of the treated group at day 15 and day 30. At the final visit, the score of a visual scale assessing the patient's global impression was also found significantly better on the combination, There was no serious side-effect. In conclusion, this study demonstrates the efficacy and safety of a combination of buzepide metiodide and haloperidol in patients with the irritable bowel syndrome.