Open Trial of Duloxetine in Outpatients With Irritable Bowel Syndrome Symptoms and Co-Morbid Major Depression

Inclusion Criteria: * Meets Diagnostic and Statistical Manual,Fourth Edition (DSM-IV) criteria for major depressive disorder (MDD) * Meets sufficient Rome III criteria for clinical symptoms of IBS * Able to give consent * Fluency in English or Spanish * Patients ages 50-65 must provide a negative colonoscopy report Exclusion Criteria: * Current suicide risk * History of psychosis, bipolar disorder, or a current diagnosis of Obsessive-Compulsive Disorder (OCD) * History of alcohol or other substance abuse or dependence in the six months prior to the study * History of non-response to an adequate trial of duloxetine * Require concurrent treatment with other psychotropic medication or other psychiatric treatment, except zolpidem for insomnia * Receive current treatment with a monoamine oxidase inhibitor (MAOI) within 14 days of visit 1 or potential need to use an MAOI during the study or within 5 days of discontinuation of study drug * Patients with uncontrolled narrow-angle glaucoma * Received electroconvulsive therapy (ECT) during the last three months * Unable to tolerate or unwillingness to accept drug-free period of varying length: 1 week for Pro Re Nata (PRN) benzodiazepines; 2 weeks for antidepressants (other than fluoxetine), buspirone, lithium, anticonvulsants, stimulants, barbiturates, opiates, regular-use benzodiazepines (except clonazepam); 5 weeks for clonazepam and fluoxetine * Clinically unstable medical disease including: Systemic hypertension of 140/90 mm Hg or more; known hypersensitivity to duloxetine or any of its inactive ingredients; liver function test values three times above the normal level; clinically significant thyroid dysfunction, (except patients who are stable on thyroid replacement therapy for at least three months) * History of chronic, persisting vomiting; rectal bleeding (melena, hematochezia, Bright Red Blood Per Rectum); severe, continuous abdominal pain; nocturnal awakening with GI symptoms; weight loss not clearly related to decreased appetite of MDD; incapacitating symptoms of IBS; severe Upper GI symptoms (e.g., heartburn) that interrupt daily activities * Family history of Ulcerative Colitis, Crohn's Disease, Celiac Disease or Colon Cancer * Clinical findings on Physical Exam or laboratory tests of: Rectal bleeding/obstruction, elevated White Blood Cell (WBC) count, unexplained anemia, abnormal Erythrocyte Sedimentation Rate (ESR), abnormal celiac disease panel * Evidence of clinically significant renal, pulmonary, cerebral vascular, cardiovascular, endocrine disorders, prostatic hypertrophy, urinary retention, laboratory abnormalities, abnormal electrocardiogram * Cancer of any type. Patients in remission for 5 years or more may be judged acceptable * Patients with current or past history of seizure disorder (except febrile seizure in childhood) * Patients who are pregnant, breast-feeding or who do not use adequate contraceptive methods. Adequate methods include birth control pills, condom plus spermicide, an intrauterine device, the Norplant system, or diaphragm. * Patients who are receiving effective medication for their depression or their IBS symptoms. Patients on effective medication for either disorder will be excluded. * Patients on antidepressants and/or anti-IBS medications at intake must still meet inclusion criteria after receiving 3 months or more of medication that was dosed following FDA guidelines. Doses must have been raised so as to produce either intolerable side effects or treatment response. * Patients who require treatment with thioridazine for any reason, at baseline and throughout the study.