What is the dosage of amoxicillin (amoxicillin) for vaginal Enterococcus faecalis infections?

Amoxicillin Dosing for Vaginal Enterococcus faecalis Infections

For uncomplicated vaginal Enterococcus faecalis infections, amoxicillin 500 mg orally every 8 hours for 7 days is the recommended first-line treatment. 1, 2

Standard Dosing Regimen

• Amoxicillin 500 mg orally three times daily (every 8 hours) for 7 days is the most effective treatment regimen for uncomplicated E. faecalis vaginal infections 2
• This dosing achieves high concentrations in urogenital tissues, making it highly effective against E. faecalis 2
• Clinical cure rates of approximately 80-90% can be expected with this regimen 2
• Ampicillin 500 mg orally every 8 hours for 7 days is an equivalent alternative with similar efficacy 3

Alternative Treatment Options

For beta-lactamase producing strains:

• Replace amoxicillin with amoxicillin-clavulanate 500 mg orally every 8 hours for 7 days 2, 3

For patients with penicillin allergy:

• Nitrofurantoin 100 mg orally every 6 hours for 7 days is an appropriate alternative 2, 3
• Fosfomycin 3 g orally as a single dose is particularly effective for uncomplicated infections 2, 3

For vancomycin-resistant E. faecalis (VRE):

• High-dose amoxicillin 500 mg orally every 8 hours may still be effective due to high urinary/vaginal concentrations 1, 2
• Linezolid 600 mg orally every 12 hours for 7-10 days if amoxicillin fails 2

Critical Clinical Considerations

Differentiate infection from colonization:

• E. faecalis may be present in vaginal cultures without causing true infection 2, 3
• Only treat symptomatic infections, not asymptomatic colonization 3

Confirm microbiological susceptibility:

• Obtain susceptibility testing before initiating therapy when possible 3
• E. faecalis is typically susceptible to amoxicillin, but resistance patterns vary 2, 3

Verify microbiological cure:

• If symptoms persist after completing treatment, confirm microbiological cure with repeat culture 2

Common Pitfalls to Avoid

• Do not underdose: Ensure the full 500 mg three times daily dosing is prescribed, not lower doses 2
• Avoid cephalosporins as monotherapy: They have minimal activity against enterococci 1
• Do not confuse with bacterial vaginosis: E. faecalis vaginal infection requires different treatment than bacterial vaginosis 2
• Do not use vancomycin empirically: Reserve for confirmed resistance to amoxicillin or severe penicillin allergy 1
• Avoid fluoroquinolones: High resistance rates (46-47%) make them inappropriate choices 3