Is IV vancomycin (intravenous vancomycin) reconstituted for oral administration effective for treating Clostridioides difficile infection (CDI)?

From the Guidelines

Intravenous vancomycin reconstituted for oral administration is not the preferred treatment for Clostridioides difficile infection (CDI), and oral vancomycin is the recommended treatment. The most recent and highest quality study, published in 2021 by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA), recommends oral vancomycin (125 mg four times daily for 10 days) as a preferred treatment for initial CDI episodes 1. While IV vancomycin can be reconstituted and administered orally in emergency situations when commercial oral vancomycin is unavailable, this practice is not ideal due to potential inconsistencies in gut concentrations and lack of FDA approval for oral use.

Key Considerations

• The IDSA and SHEA guidelines prioritize oral vancomycin, fidaxomicin, and metronidazole as treatments for CDI, with specific recommendations for initial episodes, recurrences, and fulminant cases 1.
• Oral vancomycin is effective for CDI because it remains in the gut lumen with minimal systemic absorption, achieving high local concentrations at the site of infection.
• Reconstituting IV vancomycin for oral use may be considered as a temporary measure when commercial oral vancomycin is not available, but it is not a preferred or recommended practice due to potential issues with efficacy and safety.

Treatment Recommendations

• For initial CDI episodes, oral vancomycin (125 mg four times daily for 10 days) or fidaxomicin (200 mg twice daily for 10 days) are recommended treatments 1.
• For recurrent CDI, treatments include oral vancomycin with a tapered and pulsed regimen, fidaxomicin, or a standard course of oral vancomycin followed by rifaximin 1.
• Fulminant CDI requires vancomycin administered orally or via nasogastric tube, with potential addition of intravenously administered metronidazole 1.

From the Research

Effectiveness of IV Vancomycin Reconstituted for Oral Administration

• The effectiveness of IV vancomycin reconstituted for oral administration in treating Clostridioides difficile infection (CDI) is supported by several studies 2, 3, 4, 5, 6.
• Oral vancomycin is recommended as first-line therapy for CDI, and its use has been shown to be effective in achieving clinical resolution and preventing recurrence 2, 3.
• A study published in 2019 found that fecal microbiota transplantation (FMT) combined with vancomycin was superior to fidaxomicin or vancomycin alone in treating recurrent CDI 4.
• Another study published in 2020 found that oral vancomycin did not increase the risk of vancomycin-resistant Enterococci (VRE) compared to metronidazole 5.
• Oral vancomycin prophylaxis (OVP) has also been shown to reduce the risk of recurrent CDI in high-risk patients taking systemic antibiotics 6.

Dosage and Administration

• The optimal dosage and administration of oral vancomycin for CDI treatment are not clearly defined, with varying results in clinical studies 3.
• A study published in 2020 suggested that high-dose oral vancomycin (>500 mg/day) may be effective in treating severe CDI, but more research is needed to confirm this 3.
• Vancomycin retention enema can be used in severe CDI when oral administration is not possible or in conditions where the oral formulation cannot reach the colon 3.

Safety and Efficacy

• The safety and efficacy of oral vancomycin in treating CDI have been established in several studies, with minimal adverse effects reported 2, 3, 4, 5, 6.
• However, the long-term impact of oral vancomycin on the gastrointestinal microbiome is not well understood and requires further study 6.