Augmentin Dosing for Bacterial UTI
For bacterial urinary tract infections, Augmentin (amoxicillin-clavulanate) should be dosed at 20-40 mg/kg per day divided into 3 doses for pediatric patients, or 375-500 mg three times daily for adults, with treatment duration of 7-14 days depending on infection severity and patient factors. 1
Pediatric Dosing (Febrile Infants and Children 2-24 Months)
- Dose: 20-40 mg/kg per day divided into 3 doses 1
- Duration: 7-14 days (shorter courses of 1-3 days are inferior and should not be used) 1
- Oral administration is equally efficacious to parenteral therapy in most cases 1
- Reserve parenteral therapy only for patients who appear "toxic" or cannot retain oral medications 1
Adult Dosing
Uncomplicated Cystitis (Women)
- Dose: 500 mg (amoxicillin component) with 125 mg clavulanate twice daily for 3 days 1
- However, amoxicillin-clavulanate showed lower cure rates (58%) compared to ciprofloxacin (77%) at 4-month follow-up, even among susceptible strains 1
- Consider this a second-line option when fluoroquinolones or other first-line agents cannot be used 1
Complicated UTI or Pyelonephritis
- Dose: 375-500 mg three times daily 2, 3, 4
- Duration: 7-14 days 2, 4
- Male UTIs are always considered complicated and require the longer 7-14 day duration 5
- For recurrent UTIs: 250 mg amoxicillin + 125 mg clavulanate every 8 hours for 7 days achieved 84% cure rate at 1 week and 67% at 1 month 4
Key Clinical Considerations
When to Use Augmentin
- Always obtain urine culture before initiating therapy 1, 5
- Base empiric choice on local antimicrobial susceptibility patterns 1
- Adjust therapy according to culture results 1
- Augmentin is particularly valuable for multiply-resistant organisms due to the beta-lactamase inhibitor (clavulanic acid) 3, 6
Important Caveats
- Do NOT use nitrofurantoin for febrile UTIs or pyelonephritis - it does not achieve adequate blood/tissue concentrations to treat parenchymal infection 1
- Fluoroquinolone resistance exceeding 10% in your community warrants initial parenteral therapy with ceftriaxone 1g or aminoglycoside before transitioning to oral agents 1
- Male gender automatically classifies the UTI as complicated, requiring longer treatment duration and closer monitoring 5
Monitoring and Follow-Up
- Clinical improvement should occur within 24-48 hours 1
- If no improvement or worsening occurs, switch to parenteral therapy or broader-spectrum antibiotics based on culture results 5
- Consider follow-up cultures after therapy completion to confirm eradication, especially in complicated UTIs 5
- Side effects are generally mild (gastrointestinal symptoms most common), reported in approximately 20% of patients but rarely require discontinuation 3, 4