A Placebo-Controlled Trial of Pregabalin (Lyrica) for Irritable Bowel Syndrome

Inclusion Criteria:

• Established diagnosis of Irritable Bowel Syndrome (IBS)

• Experience pain with relief with defecation

• 50/100 or greater of pain or discomfort scores during the two-week baseline period

• At least three pain attacks in a month, with at least three episodes of pain intensityequal to or exceeding 50/100

• U.S. resident

• English-speaking (able to provide consent and complete questionnaires)

• Able to participate in all aspects of the study

Exclusion Criteria:

• Known alternative/concurrent gastrointestinal diagnosis (e.g. Crohn's disease,ulcerative colitis, microscopic colitis, active celiac sprue, chronic pancreatitis orpancreatic insufficiency, scleroderma, chronic intestinal pseudo-obstruction,bacterial overgrowth, recent (<6 months) intestinal bacterial/protozoal/ parasiticinfections, HIV, active pelvic floor dysfunction, paraplegia or quadriplegia);

• Current symptoms of severe depression, as measured by Hospital Anxiety and DepressionScale (HADS) score (greater or less than 15);

• Mental retardation or any condition requiring a legal guardian;

• Current or past history of psychotic disorder (schizophrenia, bipolar disorder)

• Recent or current use (within past 30 days) of drugs that interact with Pregabalin:

• Rosiglitazone (Avandia) or Pioglitazone (Actos)

• Narcotic anti-pain medications (e.g. oxycodone, morphine)

• Anti-anxiety medications (e.g. lorazepam, alprazolam, diazepam)

• Unable to withdraw medications at least 72 hours prior to the study, because we willevaluate patient's response to pregabalin therapy for relief of IBS-associated painand disturbed sleep.

1. Non-narcotic anti-pain medications (e.g. nonsteroidal antiinflammatory drug (NSAIDs), ultram, neurontin, etc.)

2. Mexiletine, steroids, dextromethorphan.

3. Insomnia medications (e.g. benzodiazepines, zolpidem, diphenhydramine, melatonin,etc.)

• Planned surgery (especially transplant) or anesthesia exposure during trial

• Are pregnant, lactating, likely to become pregnant during medication phase and notwilling to use a reliable form of contraception (barrier contraceptives, diaphragm,injections, intrauterine device, surgical sterilization, or abstinence)

• Recent or current use (within 30 days) of Pregabalin

• Known allergy to Pregabalin

• Significant acute or chronic progressive neurologic, hepatic, renal, cardiovascular,respiratory or metabolic disease

• Recent history of alcohol or substance dependence use or abuse

• Another household member or relative participating in the study

• Professional drivers or operators of heavy machinery

• Major cardiovascular events in the last 6 months

• Use of IBS-specific drugs such as tegaserod (Zelnorm) and Lotronex (Alosetron) (within 30 days)

• Participation in another clinical trial (within 30 days)