What is the typical dosing regimen for Amoxiclav (amoxicillin-clavulanate) for bacterial infections?

Amoxiclav (Amoxicillin-Clavulanate) Dosing Regimens for Bacterial Infections

For adults with bacterial infections, the standard dosing regimen for amoxicillin-clavulanate is 875/125 mg twice daily or 500/125 mg three times daily, with the twice-daily regimen preferred due to better tolerability and similar efficacy. 1

Adult Dosing

Standard Dosing Options

• 875/125 mg twice daily (every 12 hours) - preferred regimen for most infections 1

  • Recommended for severe infections and respiratory tract infections 1
  • Associated with lower incidence of diarrhea compared to three-times-daily dosing (15% vs 14% for severe diarrhea) 1

• 500/125 mg three times daily (every 8 hours) - alternative regimen 1

  • Similar clinical efficacy to twice-daily dosing but higher incidence of diarrhea 1

Specific Infection Types

• Skin and soft tissue infections: 875/125 mg twice daily 2
• Animal or human bites: 875/125 mg twice daily 2
• Respiratory tract infections: 875/125 mg twice daily 1
• Complicated urinary tract infections: 875/125 mg twice daily 1

Special Populations

• Renal impairment: Patients with glomerular filtration rate <30 mL/min should not receive the 875 mg dose 1

Pediatric Dosing

Standard Dosing Options

• 45 mg/kg/day of amoxicillin component in 2 divided doses (twice daily) 1

  • Preferred regimen with lower incidence of diarrhea (14% vs 34%) 1

• 40 mg/kg/day of amoxicillin component in 3 divided doses (three times daily) 1

Age-Based Dosing for Co-amoxiclav

• <1 year: 2.5 mL/kg of 125/31 suspension three times daily 2
• 1-6 years: 5 mL of 125/31 suspension three times daily 2
• >6 years: 5 mL of 250/62 suspension three times daily 2

Administration Guidelines

• Take at the start of a meal to minimize gastrointestinal intolerance 1
• Enhanced absorption of clavulanate when taken with food 1
• Duration of therapy typically 7-10 days for most infections 2

Pharmacokinetic Considerations

• The twice-daily regimen (875/125 mg) provides comparable tissue concentrations to the three-times-daily regimen (500/125 mg) 3
• Time above MIC (T>MIC) is a critical pharmacodynamic parameter for amoxicillin efficacy 4
• For optimal efficacy, dosing interval should maintain plasma concentrations above the MIC for at least 40-50% of the dosing interval 4

Common Adverse Effects

• Diarrhea: Most common adverse effect (14-15%) 1
  • Lower incidence with twice-daily dosing compared to three-times-daily dosing 1
  • Severe diarrhea or withdrawal due to diarrhea: 1% for twice-daily vs 2% for three-times-daily regimen 1

Clinical Pearls

• High-dose amoxicillin-clavulanate (additional 875 mg amoxicillin) has not shown superior efficacy compared to standard-dose for acute sinusitis in adults 5
• Pharmacokinetically enhanced formulations (2000/125 mg) have been developed to maintain therapeutic plasma concentrations for longer periods, potentially improving efficacy against resistant pathogens 6
• The clavulanate component is limited to 125 mg per dose in adult formulations due to tolerability issues 7

Cautions

• Overuse may select for extended-spectrum beta-lactamase (ESBL)-producing organisms 7
• Susceptibility testing methods and interpretive criteria differ between CLSI and EUCAST 7