›Vancomycin 125 mg PO
›Every 6 hours
›Duration 10 days
›Class I recommendation aligned with guideline first line option
›Metronidazole role limitation
›Metronidazole 500 mg PO
›Every 8 hours
›Duration 10 days
›Class IIb recommendation only when fidaxomicin and vancomycin unavailable
Fulminant disease regimen
›Fulminant CDI therapy bundle
›Oral or NG vancomycin high dose
›Vancomycin 500 mg PO or NG
›Every 6 hours
›Continue until clinical improvement or definitive surgical decision
›Class I recommendation for fulminant CDI
›Rectal vancomycin if ileus
›Vancomycin 500 mg per rectum
›In 100 mL normal saline retention enema
›Every 6 hours
›Rectal administration monitoring
›Rectal irritation
›Leakage risk with poor retention
›Intravenous metronidazole adjunct
›Metronidazole 500 mg IV
›Every 8 hours
›Class I recommendation adjunct when ileus or severe systemic toxicity
›Early surgical pathway
›If shock or megacolon, urgent surgery consult
›Subtotal colectomy with end ileostomy consideration
›Diverting loop ileostomy with colonic lavage consideration
›First recurrence options
›Fidaxomicin standard regimen
›Fidaxomicin 200 mg PO
›Every 12 hours
›Duration 10 days
›Fidaxomicin extended pulsed regimen option
›Fidaxomicin 200 mg PO
›Every 12 hours for 5 days
›Then every 48 hours for 20 days
›Vancomycin taper and pulse option
›Vancomycin 125 mg PO
›Every 6 hours for 10 to 14 days
›Then every 12 hours for 7 days
›Then daily for 7 days
›Then every 48 to 72 hours for 2 to 8 weeks
›Multiple recurrences options
›Fecal microbiota therapy pathway
›After appropriate antibiotic course completion
›Recurrent episode count two or more typical threshold
›Rifaximin chaser option after vancomycin
›Rifaximin 400 mg PO
›Every 8 hours
›Duration 20 days
›Class IIb recommendation in selected recurrent cases
Adjunctive recurrence prevention
›Bezlotoxumab
›Indications
›High recurrence risk profile
›Age 65 years or older
›Immunocompromised state
›Severe CDI
›Prior CDI within 6 months
›Dosing
›Bezlotoxumab 10 mg/kg IV
›Single dose during antibiotic therapy course
›Infusion monitoring
›Hypersensitivity reaction
›Heart failure exacerbation risk in predisposed patients
›Evidence labeling
›Class IIa recommendation for recurrence risk reduction in high risk patients
›Clinical response tracking
›Stool frequency trend
›Improvement expected within 48 to 72 hours
›Abdominal distension trend
›Worsening triggers imaging and surgery reassessment
›Laboratory trend
›White blood cell count trajectory
›Creatinine trajectory
›Lactate trajectory
›Treatment failure triggers
›Persistent or worsening hypotension
›ICU escalation
›Increasing abdominal pain or peritoneal signs
›CT and surgical pathway
›Rising lactate
›Sepsis management pathway