What is the recommended dose of amoxiclav (amoxicillin-clavulanate) for treating urinary tract infections (UTIs) in adults?

Amoxicillin-Clavulanate Dosing for Adult UTIs

For uncomplicated lower urinary tract infections (cystitis) in adults, amoxicillin-clavulanate 875 mg/125 mg orally every 12 hours for 5-7 days is the recommended regimen. 1, 2, 3

Dosing by UTI Type

Lower Urinary Tract Infections (Uncomplicated Cystitis)

• Standard dose: 875 mg/125 mg orally every 12 hours 3
• Duration: 5-7 days 2
• Administration: Take at the start of meals to enhance clavulanate absorption and minimize gastrointestinal intolerance 3

Complicated UTIs and Pyelonephritis

• Standard dose: 875 mg/125 mg orally every 12 hours 3
• Duration: 5-10 days, individualized based on clinical response 2
• Alternative: 500 mg/125 mg every 8 hours (comparable efficacy but higher diarrhea rates) 3
• Clinical trials demonstrated 81% bacteriologic success at 2-4 days post-therapy with the 875 mg twice-daily regimen 3

Catheter-Associated UTIs

• Duration: 7-14 days for most patients, regardless of whether catheter remains in place 1
• Remove catheter as soon as clinically appropriate 1
• For younger women with mild CA-UTI after catheter removal, a 3-day regimen may be considered 1

Critical Considerations

Renal Impairment

• Do not use the 875 mg dose if GFR <30 mL/min 3
• Dose reduction required for severe renal impairment 3

Resistance Patterns

• Amoxicillin-clavulanate remains a first-choice option because E. coli susceptibility to this combination generally remains high, unlike plain amoxicillin (75% median resistance) 1
• Local antimicrobial resistance data should guide empiric therapy selection 2
• Perform susceptibility testing when possible to adjust therapy 2

When NOT to Use Amoxicillin-Clavulanate

• Asymptomatic bacteriuria: Treatment not recommended 2
• Multidrug-resistant organisms: Alternative agents required for ESBL-producing or carbapenem-resistant organisms 1, 2
• Severe pyelonephritis or prostatitis: Ceftriaxone/cefotaxime or ciprofloxacin preferred as first-line 1

Common Pitfalls

Adverse Effects

• Diarrhea is the most common adverse effect (15% incidence) 3
• Severe diarrhea occurs in 1% with 875 mg twice-daily dosing versus 2% with 500 mg three-times-daily dosing 3

Treatment Failure Indicators

• If no clinical response with defervescence by 72 hours, treatment may need extension and urologic evaluation may be required 1
• Consider alternative diagnosis or resistant organism if no improvement 1