Effect of Lubiprostone on Methanogenesis and Bowel Function in Chronic Constipation.

Inclusion Criteria

• •Constipation as defined by Rome III criteria13. Patients must have symptoms \> 3 days/month for the past three months and report at least two of the following symptoms ≥ 25% of the time: straining, lumpy or hard stool, sensation of incomplete evacuation, sensation of anorectal obstruction/blockage, use of manual maneuvers, \< 3 bowel movements/week. Also,they should have insufficient criteria for IBS, and only rarely loose stools without the use of laxatives.
• •≥ 3 ppm methane value at baseline1, 2(before sugar load).
• •Patients with co-morbid illnesses such as severe cardiovascular disease, chronic renal failure, or those with previous gastrointestinal surgery except cholecystectomy and appendectomy
• •Patients with neurologic diseases such as multiple sclerosis, strokes, spinal cord injuries, and those who have problems with cognizance, i.e. a mini-mental score of \<15 and/or are legally blind will be excluded.
• •Women who are pregnant or are likely to conceive during the course of the study will be excluded. Urinary pregnancy tests will be performed on all women of child-bearing potential prior to enrollment and before any x-ray of the abdomen.
• •Patients with Hirschsprung' s disease, or active local anorectal problems such as anal fissures, bleeding hemorrhoids, Crohn's, colitis, or colon cancer.
• •Patients with alternating constipation and diarrhea and those who fulfill the Rome-III criteria for irritable bowel syndrome.
• •Recent antibiotic use (last 6 weeks).
• •Patients using laxatives, PEG or Tegaserod and unwilling to discontinue these medications at least 2 weeks prior to the study.