Irritable Bowel Syndrome (IBS) Functional Magnetic Resonance Imaging (fMRI) With Desipramine

This is an interventional treatment trial for Irritable Bowel Syndrome Read More

Inclusion Criteria:

• IBS subjects with- and without comorbid somatization features will be recruited from the sources highlighted above.
• To be eligible, subjects will have to be between 18 and 90 years of age (inclusive) and qualify for a diagnosis of irritable bowel syndrome according to the criteria set forth in the Rome III criteria for the Diagnosis of Functional GI Disorders.
• IBS patients will then be assessed in terms of comorbid somatization as determined using the Patient Health Questionnaire-15 (PHQ-15).
• For this particular study, only subjects with high somatization (PHQ ≥ 10 or low somatization (PHQ ≤5) will be considered for enrollment.
• Verification of somatization status will be performed using a formal structured interview process (Diagnostic Interview Schedule, DIS).
• Persons are eligible to participate without regard to race or ethnicity.
• Given sex differences in cerebral responses to noxious stimuli and the greater prevalence of IBS in women, only female participants will be sought in this study.
• Also, in view brain hemispheric differences between left- and right-hand dominant individuals and the greater prevalence of right-handedness, all participants must be right-handed

Exclusion Criteria:

• Persons are excluded from participation for having various psychiatric, medical, and other characteristics.
• Psychiatric/cognitive exclusions include any of the following: active suicidal or homicidal ideation or a history of attempted suicide, current excessive alcohol use or other substance abuse disorders, active major depression, anxiety disorder, bipolar depression or any psychotic disorder, unwillingness to be randomized or provide informed consent, inability to communicate with staff or significant cognitive impairment.
• Medical and other exclusions include any of the following: renal or hepatic disease or impairment, diabetes, cardiovascular disease, cardiac arrythmia, cerebrovascular disease, or breastfeeding, pregnant, or imminent intention of pregnancy, history of seizures or primary neurological disorder, head trauma, brain damage, hyper- or hypothyroidism, history or abdominal surgery (other than cholecystectomy/appendectomy), or known structural GI disorder (Crohn's disease, etc.), contraindication to MRI (metallic implant, pacemaker), or rectal balloon distention (e.g., proctitis/colitis).

• Exclusions related to medications:

  1. Analgesics (narcotics, NSAIDs; acetaminophen OK)
  2. Muscle relaxants
  3. Psychoactive agents (antidepressants, antipsychotics)
  4. Other medications (phenytoin; amphetamines, prescription weight-loss drugs, or benzodiazepines)
  5. Thyroid medication
  6. Anticholinergic medications or other IBS medications (hyoscyamine, dicyclomine)
  7. Cytochrome p450 substrates
  8. Participation in any clinical trial using any other drug.