What is the recommended dose of linezolid (Zyvox) for adults with impaired renal function?

Linezolid Dosing in Renal Impairment

No dose adjustment of linezolid is required for patients with any degree of renal impairment, including those with end-stage renal disease on hemodialysis. 1

Standard Dosing Across All Renal Function Levels

• The recommended dose remains 600 mg every 12 hours (oral or IV) regardless of creatinine clearance, as the pharmacokinetics of the parent drug linezolid are not altered by renal dysfunction 1, 2
• This applies to patients with mild, moderate, or severe renal impairment, as well as those requiring hemodialysis 1

Critical Caveat: Metabolite Accumulation

While no dose adjustment is mandated, clinicians must weigh the risk of metabolite accumulation in patients with renal impairment 1:

• The two primary metabolites of linezolid accumulate progressively as renal function declines 1
• In severe renal impairment (CrCl 10-30 mL/min), metabolite A levels increase 7-fold and metabolite B levels increase 7-fold compared to normal renal function 1
• In end-stage renal disease patients on hemodialysis, metabolite exposure increases 7-8 fold 1, 3
• The clinical significance of this metabolite accumulation remains unknown, but caution is advised 1, 3

Hemodialysis Considerations

• Administer linezolid after hemodialysis sessions 1
• Approximately 30% of a linezolid dose is removed during a 3-hour hemodialysis session when started 3 hours post-dose 1
• Despite this removal, the standard 600 mg every 12 hours dosing is maintained 1

Monitoring Recommendations

Given the potential for metabolite accumulation and known adverse effects:

• Monitor complete blood counts weekly in all patients receiving linezolid for >14 days, particularly those with renal impairment 4
• Watch for reversible thrombocytopenia, which occurs in 2.4% of patients and is associated with treatment duration ≥2 weeks 4
• Consider therapeutic drug monitoring in renally impaired patients, especially those requiring prolonged therapy, as this can help optimize dosing and minimize toxicity risk 5

Practical Algorithm

1. Confirm renal function status (any degree of impairment)
2. Prescribe standard dose: 600 mg every 12 hours
3. If on hemodialysis: dose after dialysis sessions
4. Monitor CBC weekly if treatment >14 days
5. Discontinue if myelosuppression develops