Oral Treatment of Clostridioides difficile Infection with Vancomycin
For initial episodes of C. difficile infection, oral vancomycin should be administered at a dose of 125 mg four times daily for 10 days. 1
Treatment Based on Disease Severity
Non-severe C. difficile Infection
- Metronidazole 500 mg orally three times daily for 10 days is an option for non-severe cases where access to vancomycin is limited 2, 3
- Vancomycin 125 mg orally four times daily for 10 days is recommended if metronidazole cannot be used or is not preferred 2
- Low-dose vancomycin (125 mg four times daily) is as effective as high-dose vancomycin (500 mg four times daily) for non-severe cases 4
Severe C. difficile Infection
- Vancomycin 125 mg orally four times daily for 10 days is the first-line treatment 2
- Severe CDI is defined by leukocytosis (WBC >15,000 cells/mL), serum creatinine >1.5 mg/dL, or albumin <30 g/L 2, 3
- No significant difference in outcomes has been demonstrated between low-dose (125 mg four times daily) and high-dose (500 mg four times daily) vancomycin for severe CDI 5, 6
Fulminant C. difficile Infection
- Vancomycin 500 mg orally four times daily is recommended 2
- If ileus is present, add rectal vancomycin 500 mg in 100 mL normal saline every 6 hours as a retention enema 2
- Intravenous metronidazole 500 mg every 8 hours should be administered together with oral or rectal vancomycin, particularly if ileus is present 2
Treatment of Recurrent C. difficile Infection
First Recurrence
- Treat as an initial episode based on severity assessment 2
- If metronidazole was used for the initial episode, switch to vancomycin 125 mg four times daily for 10 days 2, 3
Second and Subsequent Recurrences
- Vancomycin 125 mg four times daily for at least 10 days 2
- Consider a tapered and pulsed vancomycin regimen after the initial course: 2
- Vancomycin 125 mg four times daily for 10-14 days, then
- Vancomycin 125 mg twice daily for 7 days, then
- Vancomycin 125 mg once daily for 7 days, then
- Vancomycin 125 mg every 2-3 days for 2-8 weeks 2
Important Clinical Considerations
- Discontinue the inciting antibiotic as soon as possible, as continued use significantly increases risk of recurrence 2
- Avoid antiperistaltic agents and opiates as they may mask symptoms and worsen disease 2, 3
- For patients unable to take oral medications, consider vancomycin 500 mg via nasogastric tube four times daily 2
- Recent research suggests that pulse dosing of vancomycin may not effectively clear C. difficile spores, though it remains a recommended clinical practice for recurrent infections 7, 2
- Monitor renal function in patients over 65 years of age, as nephrotoxicity can occur following oral vancomycin therapy 1
Pitfalls to Avoid
- Do not use parenteral vancomycin for C. difficile infection as it is not effective for intestinal infections 1, 2
- Avoid prolonged courses of metronidazole due to risk of cumulative and potentially irreversible neurotoxicity 2
- Do not delay treatment initiation in severe or fulminant cases while awaiting laboratory confirmation 2
- Remember that hand hygiene with soap and water (not alcohol-based sanitizers) is necessary to prevent transmission, as alcohol does not kill C. difficile spores 3