In vitro findings have established that ursodeoxycholic acid is a surrogate for deoxycholic acid in preventing the growth of C. difficile, and interrupting recurrence. Investigators will administer ursodeoxycholic acid for two months, beginning with Metronidazole and/or Vancomycin (8 to 10 days), antibiotics currently used for the treatment of acute C.Difficile infection. Ursodeoxycholic acid prevents c.difficile recurrence by (a) directly suppressing the growth of C. Difficile and (b) permitting restoration of normal fecal bile acid composition (80% deoxycholic acid) to maintain growth suppression.

The non-investigational reference therapies, Metronidazole, Vancomycin and fidaxomicin , are FDA-approved antibiotics currently in use today because of their effectiveness in suppressing the growth of C. difficile and therefore quickly eliminating the colitis and diarrhea. However, they do not promote the restoration of the normal bacterial flora. Therefore, when medication is stopped, the C. difficile colitis returns. In vitro findings have established that ursodeoxycholic acid is a surrogate for deoxycholic acid in preventing the growth of C. difficile, and interrupting recurrence.

Inclusion Criteria:

• Male and female patients with recurrent C. difficile colitis
• 18 years of age and older
• Capable of giving informed consent

Exclusion Criteria:

• Patients with other gastrointestinal problems prone to cause diarrhea if they cannot be controlled for the period of the study. Lactose intolerance or gluten enteropathy are not an exclusion provide that the potential subject is asymptomatic and can be expected to adhere to the appropriate dietary regimen.
• Patients with contraindications to metronidazole or vancomycin and/or ursodiol tablets or components of the formulations.
• Patients not available for long-term follow-up (2 months) by their physician will be excluded from the study.

8 weeks