Is Vancomycin Dialyzable in Hemodialysis Patients?
Yes, vancomycin is significantly dialyzable during hemodialysis, particularly with high-flux membranes, with approximately 25-40% of the drug removed during a typical dialysis session. 1, 2, 3
Evidence of Dialyzability
Removal During Hemodialysis
- High-flux hemodialysis removes 33.4-39.5% of vancomycin during a 3-4 hour dialysis session, which is clinically significant and necessitates supplemental dosing. 2
- The FDA label explicitly states that "vancomycin is poorly removed by dialysis" in the context of conventional low-flux dialysis, but this statement is outdated and does not reflect modern high-flux hemodialysis practices. 1
- Hemofiltration and hemoperfusion with polysulfone resin result in increased vancomycin clearance beyond standard dialysis. 1
Impact on Dosing Strategy
- When vancomycin is administered during the last hour of dialysis (intradialytic dosing), exposure decreases by approximately 25% compared to post-dialysis administration, requiring dose adjustments to maintain therapeutic levels. 4
- Studies using high-flux membranes demonstrate that once-weekly dosing results in 77% of levels falling below 10 mcg/mL by day 5 and 84% by day 7, confirming substantial dialytic removal. 3
Clinical Implications
Recommended Dosing Approach
- The Infectious Diseases Society of America recommends a loading dose of 20 mg/kg administered during the last hour of dialysis, followed by 500 mg maintenance doses during the last 30 minutes of each subsequent dialysis session. 5, 6
- For intradialytic administration over the last 2 hours of dialysis, a 30 mg/kg dose achieves similar predialysis concentrations as conventional 15 mg/kg post-dialysis dosing. 2
Monitoring Requirements
- Target predialysis vancomycin levels should be maintained at 10-25 mg/L for serious gram-positive infections including MRSA bacteremia and catheter-related bloodstream infections. 5
- Monitoring should occur twice weekly in hemodialysis patients, particularly when using high-flux membranes or higher doses. 5
Common Pitfalls to Avoid
- Do not assume vancomycin is non-dialyzable based on older literature or low-flux dialysis data—modern high-flux membranes remove substantial amounts of the drug. 3
- Avoid once-weekly dosing regimens in high-flux hemodialysis settings, as they consistently result in subtherapeutic levels within 5-7 days. 3
- Do not administer vancomycin post-dialysis if intradialytic administration is feasible, as this unnecessarily prolongs patient time in the dialysis unit and may compromise vascular access preservation. 2, 4