What is the renal dose adjustment for Augmentin (amoxicillin-clavulanate) in patients with impaired renal function?

Renal Dose Adjustments for Augmentin (Amoxicillin-Clavulanate)

For patients with severe renal impairment (GFR <30 mL/min), avoid the 875/125 mg formulation entirely and use either 500/125 mg or 250/125 mg every 12 hours for GFR 10-30 mL/min, or every 24 hours for GFR <10 mL/min, with an additional dose during and after hemodialysis. 1

Dosing Algorithm by Renal Function

Normal to Mild Renal Impairment (GFR >30 mL/min)

• No dose adjustment required - use standard dosing regimens 1
• Standard adult doses remain appropriate (500/125 mg three times daily or 875/125 mg twice daily) 1

Moderate Renal Impairment (GFR 10-30 mL/min)

• The 875/125 mg dose is contraindicated in this population 1
• Use 500/125 mg or 250/125 mg every 12 hours, selecting strength based on infection severity 1
• This represents approximately a 50% reduction in dosing frequency compared to normal renal function 2

Severe Renal Impairment (GFR <10 mL/min)

• Use 500/125 mg or 250/125 mg every 24 hours, depending on infection severity 1
• This extends the dosing interval to once daily rather than reducing individual dose strength 1

Hemodialysis Patients

• Administer 500/125 mg or 250/125 mg every 24 hours based on severity 1
• Critical timing consideration: Give an additional dose both during dialysis and at the end of the dialysis session 1
• Post-dialysis dosing ensures adequate drug exposure and allows for direct observation 2
• Administering before dialysis wastes medication and leaves patients undertreated 2

Key Clinical Considerations

Formulation Equivalency Warnings

• Two 250/125 mg tablets do NOT equal one 500/125 mg tablet because both contain the same 125 mg of clavulanic acid 1
• The 250/125 mg tablet and 250/62.5 mg chewable tablet are not interchangeable due to different clavulanic acid content 1
• Substitution errors can lead to clavulanic acid overdosing and increased gastrointestinal side effects 1

Rationale for Interval Extension vs. Dose Reduction

• The FDA label prioritizes extending dosing intervals rather than reducing individual doses 1
• This approach maintains peak drug concentrations while accounting for reduced renal clearance 2
• Maintaining dose strength is particularly important for concentration-dependent efficacy 3

Monitoring Requirements

• Patients with borderline renal function may require 24-hour urine collection to accurately define the degree of impairment before making regimen changes 4
• Close monitoring for adverse effects is warranted, as drug accumulation can occur with any degree of renal insufficiency 4

Common Pitfalls to Avoid

• Do not assume all antibiotics require identical renal adjustments - amoxicillin-clavulanate has specific requirements distinct from other beta-lactams 2
• Do not use the 875/125 mg formulation in patients with GFR <30 mL/min - this is explicitly contraindicated 1
• Do not forget supplemental dosing with hemodialysis - both intradialytic and post-dialysis doses are required 1
• Do not substitute tablet formulations without accounting for clavulanic acid content - this can lead to dosing errors 1