Standard Augmentin Dosing
For adults with mild-to-moderate infections, the standard dose is 500 mg amoxicillin/125 mg clavulanate three times daily or 875 mg/125 mg twice daily for 7-10 days, while high-dose therapy (2000 mg/125 mg twice daily) is reserved for respiratory infections with risk factors for resistant pathogens. 1
Adult Dosing Regimens
Standard-Dose Options
- 500 mg/125 mg three times daily: Provides adequate coverage for mild-to-moderate infections including uncomplicated respiratory tract infections, skin and soft tissue infections, and urinary tract infections 2
- 875 mg/125 mg twice daily: Specifically recommended for respiratory infections (acute bacterial rhinosinusitis, community-acquired pneumonia, acute exacerbations of chronic bronchitis) and offers the advantage of twice-daily dosing with less gastrointestinal side effects (1% vs 2% severe diarrhea, p<0.05) 2
High-Dose Therapy (2000 mg/125 mg twice daily)
High-dose amoxicillin-clavulanate is indicated when any of the following risk factors are present 1:
- Recent antibiotic use within 4-6 weeks
- Age over 65 years
- Moderate to severe infection
- Immunocompromised status
- Comorbidities (diabetes, heart disease, lung disease)
- High local prevalence of penicillin-resistant Streptococcus pneumoniae (>10%)
- Failed previous antibiotic therapy
- Smokers or exposure to secondhand smoke
- Close contact with children in daycare
Clinical efficacy: High-dose formulations achieve 90-92% predicted clinical success versus 83-88% for standard doses when risk factors are present 1
Pediatric Dosing
Standard Pediatric Dose
- 45 mg/kg/day of amoxicillin component with 6.4 mg/kg/day of clavulanate, divided into 2 doses for uncomplicated infections 1
High-Dose Pediatric Regimen
80-90 mg/kg/day of amoxicillin with 6.4 mg/kg/day of clavulanate, divided into 2 doses when the following risk factors are present 1:
- Age under 2 years
- Daycare attendance
- Recent antibiotic treatment (within 30 days)
- Concurrent conjunctivitis (suggests Moraxella catarrhalis)
- Pneumonia not responding to amoxicillin alone
- High local prevalence of resistant S. pneumoniae (>10%)
Maximum daily dose: 4000 mg/day of amoxicillin component 1
Important formulation note: The 14:1 ratio of amoxicillin to clavulanate in high-dose pediatric formulations causes less diarrhea than other ratios 1
Weight-Based Transition
For patients weighing ≥40 kg, use adult dosing rather than pediatric weight-based calculations to avoid dosing errors 1
Treatment Duration by Indication
Respiratory Infections
- Acute bacterial sinusitis (adults): 5-7 days 1, 2
- Acute bacterial sinusitis (children): 10-14 days 1
- Community-acquired pneumonia: 5-7 days if afebrile for 48 hours and clinically stable 2
- Bronchiectasis exacerbations: 14 days 1
Other Infections
- Skin and soft tissue infections: 7-10 days 2
- Animal or human bites: 500 mg/125 mg twice daily for 7-10 days 2
- Urinary tract infections: 7-10 days 3
Critical Dosing Considerations
Formulation Equivalency Warning
Never substitute two 250 mg tablets for one 500 mg tablet, as this results in excessive clavulanate dosing and increased gastrointestinal side effects 2
Reassessment Protocol
If no clinical improvement occurs after 72 hours of therapy, consider 1:
- Changing antibiotic class
- Obtaining cultures
- Imaging studies (CT scan for sinusitis)
- Endoscopic evaluation
- Inadequate source control (abscess requiring drainage)
Penicillin Allergy Alternatives
For patients with penicillin allergy 1:
- Adults: Doxycycline or respiratory fluoroquinolones (levofloxacin, moxifloxacin)
- Children with non-type I allergy: Clindamycin plus third-generation oral cephalosporin
Common Pitfalls to Avoid
Underdosing in high-risk patients: Standard doses have 20-25% failure rates when risk factors for resistant organisms are present; always use high-dose therapy when indicated 1
Incorrect pediatric dosing: For children ≥40 kg, use adult dosing schedules rather than weight-based calculations 1
Inadequate treatment duration: While 5-7 days is effective for uncomplicated adult sinusitis, children require 10-14 days to prevent relapse 1
Ignoring local resistance patterns: In areas with >10% penicillin-resistant S. pneumoniae, always use high-dose formulations 1