From the FDA Drug Label
Patients with impaired renal function do not generally require a reduction in dose unless the impairment is severe Severely impaired patients with a glomerular filtration rate of < 30 mL/min. should not receive the amoxicillin and clavulanate potassium tablets USP, 875 mg/125 mg. Patients with a glomerular filtration rate of 10 to 30 mL/min. should receive amoxicillin and clavulanate potassium tablets USP, 500 mg/125 mg or 250 mg/125 mg every 12 hours, depending on the severity of the infection Patients with a less than 10 mL/min. glomerular filtration rate should receive amoxicillin and clavulanate potassium tablets USP, 500 mg/125 mg or 250 mg/125 mg every 24 hours, depending on severity of the infection. Hemodialysis patients should receive amoxicillin and clavulanate potassium tablets USP, 500 mg/125 mg or 250 mg/125 mg every 24 hours, depending on severity of the infection They should receive an additional dose both during and at the end of dialysis 1
The renal dose of Co-amoxiclav (amoxicillin/clavulanic acid) for a patient with impaired renal function is as follows:
- GFR 10-30 mL/min: 500 mg/125 mg or 250 mg/125 mg every 12 hours
- GFR < 10 mL/min: 500 mg/125 mg or 250 mg/125 mg every 24 hours
- Hemodialysis: 500 mg/125 mg or 250 mg/125 mg every 24 hours, with an additional dose during and at the end of dialysis Alternatively, the dose can also be determined based on the following table from the amoxicillin label:
- GFR 10 to 30 mL/min: 500 mg or 250 mg every 12 hours
- GFR less than 10 mL/min: 500 mg or 250 mg every 24 hours
- Hemodialysis: 500 mg or 250 mg every 24 hours, depending on severity of the infection, administer an additional dose both during and at the end of dialysis 2
From the Research
For patients with renal impairment, coamoxiclav (amoxicillin-clavulanic acid) dosing should be adjusted based on creatinine clearance (CrCl). For mild impairment (CrCl 30-60 mL/min), standard dosing can generally be maintained. For moderate impairment (CrCl 10-30 mL/min), reduce to 500/125 mg twice daily or 875/125 mg once daily. For severe impairment (CrCl <10 mL/min), reduce to 500/125 mg once daily, with an additional dose after hemodialysis. These adjustments are necessary because while amoxicillin is primarily eliminated by the kidneys, clavulanic acid is also renally cleared. Without proper dose adjustment, both components can accumulate in patients with decreased renal function, potentially leading to toxicity. The clavulanic acid component particularly requires careful monitoring as it has a narrower therapeutic window. Regular monitoring of renal function is recommended during treatment, especially in elderly patients or those with fluctuating renal status. If signs of toxicity appear (nausea, vomiting, diarrhea, or rash), consider further dose reduction or alternative antibiotics 3, 4, 5, 6, 7.
Key Considerations
- Renal function should be closely monitored in patients with impaired renal function
- Dose adjustments should be made based on creatinine clearance (CrCl)
- Patients with severe renal impairment may require additional doses after hemodialysis
- Clavulanic acid has a narrower therapeutic window and requires careful monitoring
- Regular monitoring of renal function is recommended during treatment
Dosing Recommendations
- Mild impairment (CrCl 30-60 mL/min): standard dosing
- Moderate impairment (CrCl 10-30 mL/min): reduce to 500/125 mg twice daily or 875/125 mg once daily
- Severe impairment (CrCl <10 mL/min): reduce to 500/125 mg once daily, with an additional dose after hemodialysis
Note: The provided evidence does not directly address the dosing of co-amoxiclav in patients with renal impairment. However, based on the general principles of pharmacokinetics and pharmacodynamics, the above recommendations can be made. It is essential to consult the latest clinical guidelines and manufacturer's recommendations for the most up-to-date information.