Augmentin Dosage for Urinary Tract Infections
For treating urinary tract infections, Augmentin (amoxicillin/clavulanate) should be dosed at 375 mg (250 mg amoxicillin/125 mg clavulanate) three times daily for 5-7 days.
Dosing Recommendations Based on UTI Type
Uncomplicated UTI/Cystitis
- Standard dose: 375 mg (250 mg amoxicillin/125 mg clavulanate) three times daily
- Duration: 5 days
- Timing: Take with meals to minimize gastrointestinal side effects
Complicated UTI
- Standard dose: 375 mg (250 mg amoxicillin/125 mg clavulanate) three times daily
- Duration: 7-10 days
- Alternative dosing: 625 mg (500 mg amoxicillin/125 mg clavulanate) three times daily may be considered for more severe infections
Evidence Supporting These Recommendations
Clinical studies have demonstrated good efficacy with the 375 mg three times daily dosing regimen for UTIs. In a study of patients with recurrent UTIs, this dosing achieved microbiological cure rates of 84% one week after treatment and 67% one month later 1. Another study comparing Augmentin to amoxicillin alone in elderly patients with UTIs showed an 87.5% response rate with Augmentin versus only 43% with amoxicillin 2.
For complicated UTIs, a 5-day course of clavulanate-potentiated amoxicillin has shown cure rates of 72% at 5-10 days post-treatment 3. In patients with spinal injuries and UTIs caused by amoxicillin-resistant organisms, Augmentin 375 mg three times daily for 5 days achieved a 100% bacteriological success rate 24 hours after therapy 4.
Important Considerations
Resistance Patterns
- Augmentin is particularly valuable for UTIs caused by beta-lactamase-producing organisms that would be resistant to amoxicillin alone
- The addition of clavulanic acid effectively reduces resistance in most Gram-negative urinary pathogens 5
Administration
- Always take with food to reduce gastrointestinal side effects
- Complete the full course of antibiotics even if symptoms improve
Monitoring
- Assess clinical response within 48-72 hours
- If symptoms persist beyond 72 hours, reevaluate and consider urine culture and susceptibility testing
Side Effects
- Gastrointestinal effects (diarrhea, nausea) are most common (8-12% of patients)
- Side effects are generally mild and rarely require discontinuation of treatment 1
Alternative Treatments
If Augmentin cannot be used due to allergies or resistance concerns, guidelines recommend considering:
- Fluoroquinolones (if local resistance is <10%)
- Trimethoprim-sulfamethoxazole (if local resistance is <20%)
- Nitrofurantoin (for uncomplicated lower UTIs only)
- Fosfomycin (for uncomplicated lower UTIs only)
Special Populations
Elderly Patients
- Standard dosing is generally appropriate
- Monitor renal function and adjust dose if needed
- Augmentin has shown good efficacy (87.5% response rate) in elderly populations 2
Patients with Renal Impairment
- Dose adjustment required based on creatinine clearance
- For severe renal impairment (CrCl <30 ml/min), consider reducing to twice daily dosing or using a lower strength formulation
Remember that obtaining a urine culture before starting antibiotics is recommended, particularly for complicated UTIs, recurrent infections, or treatment failures, to guide appropriate therapy based on susceptibility results.