Conditions: Chronic Constipation, Methanogenesis
Allocation: RANDOMIZED | Intervention model: SINGLE_GROUP
Enrollment: 41
Healthy volunteers: no

Brief summary:
Lubiprostone, a chloride channel activator, has been shown to improve symptoms of chronic constipation, largely by enhancing chloride-rich intestinal fluid secretion. Whether Lubiprostone has effects on colonic methanogenesis is not known. The investigators hypothesize that the effects of Lubiprostone may in part be due to its effects on altering colonic flora, particularly methanogenic flora.

By altering the colonic stasis of stool and through more efficient clearance of digestive residue, the investigators anticipate that Lubiprostone may either inhibit or promote better excretion of methanogenic flora, and thereby decrease the gut load of methane producing bacteria. In turn, this may lead to enhanced colonic smooth muscle contraction and an increased rate of spontaneous bowel movements and reduction of constipation symptoms.

The aim is to investigate the effects of Lubiprostone on intestinal methane production and bowel symptoms in patients with chronic constipation, by performing a randomized, double blind, placebo controlled study.

Detailed description:

Arms:
arm 1: 24mcg BID for 4 weeks, oral medication arm 2: 24mcg BID for 4 weeks (placebo), oral medication

Interventions: intervention 1: Lubiprostone intervention 2: Lubiprostone Control
Intervention descriptions: intervention 1: Colonic transit study performed and stool/symptom diaries will be reviewed. Eligible subjects will be given a lactulose breath test and randomized to Lubiprostone or placebo. Treatment group receives 24 mcg Lubiprostone twice daily and placebo group receives pills (identical in appearance to the study drug) for one month. Subjects will be asked to maintain a daily stool/symptom diary for duration of the study. In the middle of the study a research coordinator will call the subjects to take questions/concerns and record adverse events. Lactulose breath test will be repeated, constipation questionnaire filled out, colon transit study performed. intervention 2: Colonic transit study performed and stool/symptom diaries will be reviewed. Eligible subjects will be given a lactulose breath test and randomized to Lubiprostone or placebo. Treatment group receives 24 mcg Lubiprostone twice daily and placebo group receives pills (identical in appearance to the study drug) for one month. Subjects will be asked to maintain a daily stool/symptom diary for duration of the study. In the middle of the study a research coordinator will call the subjects to take questions/concerns and record adverse events. Lactulose breath test will be repeated, constipation questionnaire filled out, colon transit study performed.

Protocol document: