What are the dosing recommendations for Augmentin (amoxicillin-clavulanate) in patients with impaired renal function?

Augmentin Renal Dosing Recommendations

For patients with impaired renal function, Augmentin dosing must be adjusted based on glomerular filtration rate (GFR), with standard dosing maintained for GFR >30 mL/min, reduced dosing or extended intervals for GFR 10-30 mL/min, and once-daily dosing for GFR <10 mL/min, with hemodialysis patients requiring an additional dose during and after dialysis. 1

Dosing Algorithm by Renal Function

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

• No dose adjustment required - standard dosing regimens can be used 2
• The 875 mg/125 mg formulation is appropriate in this population 1

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

• Patients should NOT receive the 875 mg/125 mg dose 1
• Administer 500 mg/125 mg or 250 mg/125 mg every 12 hours, with the specific dose depending on infection severity 1
• This represents approximately a 50% dose reduction or doubling of the dosing interval compared to standard dosing 2

Severe Renal Impairment (GFR <10 mL/min)

• Administer 500 mg/125 mg or 250 mg/125 mg every 24 hours, based on infection severity 1
• This represents a 25-50% reduction from normal dosing 2

Hemodialysis Patients

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

Special Monitoring Considerations

Borderline Renal Function

• Patients with borderline renal function may require 24-hour urine collection to accurately define the degree of impairment before making regimen changes 2
• This is particularly important when GFR estimates are near threshold values (around 30 mL/min)

Ongoing Monitoring

• Close monitoring for adverse effects is warranted, as drug accumulation can occur with any degree of renal insufficiency 2
• The clavulanate component can accumulate and potentially cause toxicity in renal impairment 2

Critical Formulation Considerations

Non-Interchangeable Formulations

• Two 250 mg/125 mg tablets should NOT be substituted for one 500 mg/125 mg tablet because both contain the same amount of clavulanic acid (125 mg), making them non-equivalent 1
• The 250 mg/125 mg tablet and 250 mg/62.5 mg chewable tablet are NOT interchangeable due to different clavulanic acid content 1
• This is a common prescribing error that can lead to clavulanate overdosing in renal impairment

Common Pitfalls to Avoid

• Do not assume all antibiotics require the same degree of dosage adjustment - individualized adjustments based on specific drug properties are necessary 2
• Do not use the 875 mg/125 mg formulation in patients with GFR <30 mL/min - this is explicitly contraindicated 1
• Do not administer doses before hemodialysis - this results in drug removal and subtherapeutic levels 2
• Do not overlook the need for supplemental dosing after dialysis - failure to provide additional doses leaves patients undertreated 1