Conditions: Diarrhea Predominant Irritable Bowel Syndrome
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 13
Healthy volunteers: no

Brief summary:
The investigators' hypothesis is that therapy with Colesevelam, reduces fecal bile acid excretion in patients with Irritable Bowel Syndrome (IBS)-diarrhea with prior evidence of increased fecal 48 hour total bile acid excretion. The investigators aim to study the ability of the HPLC assay for fecal bile acids to demonstrate responsiveness after treatment with Colesevelam.

Detailed description:
This study will evaluate whether Colesevelam, a bile acid sequestrant, is able to reduce fecal bile acids and improve bowel function in patients with IBS-diarrhea and Mayo's HPLC method can demonstrate a response to the Colesevelam.

The study design will be a single center, unblinded, single dose trial to study the ability to identify the effect of taking 1875 mg (3 tablets \[625 mg/tablet\]) of Colesevelam orally twice daily for ten days on fasting serum 7alphaC4 and total 48 hour fecal bile acid excretion. Stool and fasting serum samples will be collected predose and during final 48 hours' dosing for assessment. Participants will also fill out an 8-day stool diary assessing frequency, consistency, ease of passage of bowel movements before and during treatment with Colesevelam.

Arms:
arm 1: 1875 mg of Colesevelam orally twice daily for 10 days

Interventions: intervention 1: Colesevelam
Intervention descriptions: intervention 1: Subjects will receive 1875 mg of Colesevelam orally twice daily for 10 days

Protocol document: