Patients with severe-complicated disease that would compromise oral therapy (hypotenstion or shock, ileus or bowel obstruction, megacolon).
Patients with an allergy to oral vancomycin or fidaxomicin.
Patients anticipated to receive metronidazole after enrollment.
Patients who already received oral vancomycin or metronidazole (either oral or intravenous) for > 24 hours within the preceding 72 hours at the time of enrollment.
Patients anticipated to receive adjunctive C. difficile therapy (rifaxamin, nitazoxanide, tigecycline) after enrollment.

NCT02692651_exc_T1
Condition
hypotenstion
NCT02692651_exc_T2
Condition
shock
NCT02692651_exc_T3
Condition
ileus
NCT02692651_exc_T4
Condition
bowel obstruction
NCT02692651_exc_T5
Condition
megacolon
NCT02692651_exc_T7
Condition
allergy
NCT02692651_exc_T8
Drug
vancomycin
NCT02692651_exc_T9
Drug
fidaxomicin
NCT02692651_exc_T10
Qualifier
oral
NCT02692651_exc_T11
Scope
vancomycin or fidaxomicin
NCT02692651_exc_T12
Drug
metronidazole
NCT02692651_exc_T13
Mood
anticipated
NCT02692651_exc_T14
Drug
vancomycin
NCT02692651_exc_T15
Drug
metronidazole
NCT02692651_exc_T16
Qualifier
oral
NCT02692651_exc_T17
Multiplier
> 24 hours
NCT02692651_exc_T18
Temporal
preceding 72 hours at the time of enrollment.
NCT02692651_exc_T19
Reference_point
enrollment
NCT02692651_exc_T20
Scope
oral vancomycin or metronidazole
NCT02692651_exc_T21
Mood
anticipated
NCT02692651_exc_T22
Procedure
C. difficile therapy
NCT02692651_exc_T23
Drug
rifaxamin
NCT02692651_exc_T24
Drug
nitazoxanide
NCT02692651_exc_T25
Drug
tigecycline
NCT02692651_exc_T26
Scope
rifaxamin, nitazoxanide, tigecycline)