Prolonged Taper of Oral Vancomycin for Recurrent C. difficile Infection
For patients with recurrent C. difficile infection, use oral vancomycin in a tapered and pulsed regimen: 125 mg four times daily for 10-14 days, then 125 mg twice daily for 7 days, then 125 mg once daily for 7 days, then 125 mg every 2-3 days for 2-8 weeks. 1
When to Use the Prolonged Taper Regimen
First Recurrence:
- Use the tapered and pulsed vancomycin regimen if a standard 10-day vancomycin course was used for the initial episode 1
- This approach is preferred over repeating another standard 10-day course 1
- Alternative options include fidaxomicin 200 mg twice daily for 10 days or standard vancomycin if metronidazole was used initially 1
Second or Subsequent Recurrences:
- The tapered and pulsed vancomycin regimen is a primary treatment option 1
- Other options include vancomycin 125 mg four times daily for 10 days followed by rifaximin 400 mg three times daily for 20 days, fidaxomicin, or fecal microbiota transplantation 1
- Consider FMT after at least 2 recurrences (3 total CDI episodes) with failed antibiotic treatments 1, 2
Rationale for the Taper-and-Pulse Strategy
The prolonged taper works by keeping C. difficile vegetative forms suppressed while allowing restoration of normal gut microbiota 1. Standard 10-day courses kill vegetative bacteria but not spores, which can germinate after treatment ends and cause recurrence 1. The gradual reduction in vancomycin frequency provides ongoing suppression during microbiota recovery 1.
Dosing Considerations
Standard dose is sufficient: 125 mg is as effective as 500 mg for non-fulminant disease 3. Higher doses (500 mg four times daily) are reserved for fulminant CDI with hypotension, shock, ileus, or megacolon 1.
Systemic absorption warning: Patients with inflammatory intestinal mucosa may have significant systemic vancomycin absorption 4. Monitor serum vancomycin levels in patients with renal insufficiency, severe colitis, or those receiving concomitant aminoglycosides 4.
Common Pitfalls to Avoid
Do not use metronidazole for recurrent CDI: Metronidazole has lower sustained response rates than vancomycin and carries risk of cumulative neurotoxicity with prolonged use 1, 2. It should only be considered for initial non-severe episodes when vancomycin/fidaxomicin access is limited 1.
Do not treat asymptomatic carriers: Testing or treating asymptomatic patients after treatment completion is not recommended 5. Approximately 50% of patients remain stool culture-positive for weeks after successful treatment without symptoms 3.
Monitor elderly patients closely: Nephrotoxicity risk increases in patients >65 years, even with normal baseline renal function 4. Monitor renal function during and after oral vancomycin therapy in this population 4.
Alternative and Adjunctive Therapies
Bezlotoxumab: Consider adding this monoclonal antibody against C. difficile toxin B for patients with high recurrence risk, including those with 027 epidemic strain, immunocompromised status, or severe presentation 2.
Rifaximin combination: For multiply recurrent disease, vancomycin 125 mg four times daily for 10 days followed by rifaximin 400 mg three times daily for 20 days reduced recurrence from 31% to 15% in one trial 1.
Fecal microbiota transplantation: This is highly effective for multiple recurrences and should be offered after appropriate antibiotic trials have failed 1, 2.
Special Situations
Fulminant disease despite standard therapy: Escalate to vancomycin 500 mg orally four times daily plus intravenous metronidazole 500 mg every 8 hours 1, 2. If ileus is present, add rectal vancomycin 500 mg in 100 mL normal saline every 6 hours 1, 2.
Concomitant antibiotic needs: Patients requiring other antibiotics during or shortly after CDI treatment have higher recurrence risk 1. Some clinicians extend vancomycin at lower doses (e.g., 125 mg once daily) until other antibiotics are completed, though evidence for this practice is limited 1.