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

Lyrica is the trade name for pregabalin, which was first approved by the FDA in June 2005
and has been available through prescription since fall 2005, and is marketed by Pfizer.
Lyrica is known to have clinical efficacy treating pain disorders including irritable bowel
syndrome-related conditions such as fibromyalgia.

Inclusion Criteria:

- Established diagnosis of 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
intensity equal to or exceeding 50/100

- 18-70 years of age

- 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 or
pancreatic insufficiency, scleroderma, chronic intestinal pseudo-obstruction,
bacterial overgrowth, recent (<6 months) intestinal bacterial/protozoal/ parasitic
infections, HIV, active pelvic floor dysfunction, paraplegia or quadriplegia);

- Current symptoms of severe depression, as measured by Hospital Anxiety and Depression
Scale (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 will
evaluate patient's response to pregabalin therapy for relief of IBS-associated pain
and 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 not
willing 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)