Eligibility Criteria:
Inclusion Criteria:
* Normal esophagogastroduodenoscopy (EGD) (no esophagitis, Barrett's esophagus, cancer, erosions, or ulcer disease) within the past 5 years
* Diagnosis of functional dyspepsia
* Patients may have failed to adequately respond to antisecretory therapy in the past for functional dyspepsia to be suitable; a good response to antisecretory therapy, which remains first line therapy, suggests underlying gastroesophageal reflux disease (GERD).
Exclusion Criteria:
* Any documented history of endoscopic esophagitis, or predominant heartburn or acid regurgitation, or these symptoms two or more times per week in the prior year, to exclude GERD.
* Those who have had an adequate response to antisecretory therapy according to the physician interview, to exclude patients with disease easy to control with first line therapy or misdiagnosed GERD.
* Any documented peptic ulcer disease.
* Regular use of non-steroidal anti-inflammatory drugs (except long term low dose aspirin ≤ 325 mg / day)
* Subjects undergoing psychiatric treatment, having a current history of drug or alcohol abuse, or currently taking psychotropic medication for depression or psychosis, or eating disorders
* A history of abdominal surgery except appendectomy, cholecystectomy or hysterectomy, tubal ligations, bladder slings, and vasectomies
* Subjects with concurrent major physical illness (including cardiac or liver disease, diabetes, inflammatory bowel disease, glaucoma, urinary retention, active thyroid disease, vasculitis, lactose intolerance explaining symptoms)
* Subjects whose literacy skills are insufficient to complete self report questionnaires.
* Pregnancy, or refusal to apply adequate contraceptive measures during the trial
* Subjects currently on antidepressant therapy will be excluded.
* Patients who score 11 or greater on the 7 questions related to depression of the Hospital Anxiety Depression Scale will be excluded. These patients will be encouraged to get follow up for depression.
* All eligible patients over age 50 will have an EKG before randomization. Those found to have significant arrhythmias, conduction defects or a previous myocardial infarction on EKG will be excluded. Anyone with QT prolongation will be excluded.
The following concomitant medications will be prohibited during the trial:
* Systemically acting cholinergics and anticholinergics (atropine, didinium bromide, propantheline)
* Prokinetics (e.g., metoclopramide, tegaserod)
* Macrolide antibiotics (e.g., erythromycin, azithromycin)
* Aspirin (\> 325 mg/day)
* Spasmolytics (e.g., dicyclomine)
* Antidepressants other than study medications
* Serotonin enhancing drugs: monamine oxidase inhibitors, anticonvulsants, dextromethorphan.
Participants will be instructed to avoid grapefruit/grapefruit juice during the trial.