 We plan to study 15 male and female subjects between the ages of 18 and 65 years who have had gastrointestinal symptoms at least 2 daysweek for greater than six months and who have been diagnosed with IBS by a physician. During the 12-week study, subjects will receive open-label duloxetine titrated up to 60mgday. Subjects will be asked to complete a total of ten study visits during the 12-week study period. All study visits will be conducted at McLean Hospital. 