Recommended Dosage of Co-amoxiclav for Urinary Tract Infections
For adults with uncomplicated UTIs, co-amoxiclav (amoxicillin-clavulanate) should be dosed at 875 mg amoxicillin/125 mg clavulanic acid every 12 hours for 5-10 days. 1, 2
Adult Dosing Regimens
- For uncomplicated UTIs: 875 mg amoxicillin/125 mg clavulanate every 12 hours for 5-10 days 1, 2
- Alternative regimen: 500 mg amoxicillin/125 mg clavulanate every 8 hours for 5-10 days 1
- For complicated UTIs or pyelonephritis: 875 mg amoxicillin/125 mg clavulanate every 12 hours for 7-14 days 1, 2
Pediatric Dosing
- For children: 20-40 mg/kg/day divided into 3 doses 3, 2
- Treatment duration for pediatric UTIs should be 7-14 days 3
Clinical Evidence
- FDA clinical studies show comparable efficacy between 875 mg q12h and 500 mg q8h dosing regimens for complicated UTIs 1
- The 875 mg q12h regimen showed significantly lower rates of severe diarrhea (1.0%) compared to the 500 mg q8h regimen (2.5%) 1
- Bacteriological success rates were similar between both dosing regimens at 2-4 days post-therapy (81% for 875 mg q12h vs 80% for 500 mg q8h) 1
Special Considerations
- For recurrent UTIs, a regimen of 250 mg amoxicillin/125 mg clavulanic acid every 8 hours for 7 days has shown 84% microbiological cure rates one week after treatment 4
- For ESBL-producing organisms causing recurrent UTIs, higher doses may be considered (e.g., 875 mg amoxicillin/125 mg clavulanic acid twice daily) 5
- Local antimicrobial resistance patterns should guide empiric therapy selection 2
- Co-amoxiclav should not be used as empiric therapy for hospitalized patients with pyelonephritis or complicated UTIs due to inadequate coverage of potential pathogens 6
Common Pitfalls and Caveats
- Co-amoxiclav is not recommended for asymptomatic bacteriuria 2
- Gastrointestinal side effects are common, particularly with higher doses of clavulanic acid 7
- For UTIs caused by multidrug-resistant organisms, alternative agents may be required 3, 2
- For uncomplicated UTIs in patients >65 years, males, or those with underlying risk conditions, a 10-day course is preferred over shorter regimens 8
- Susceptibility testing should be performed when possible to adjust therapy accordingly 2