Augmentin (Amoxicillin/Clavulanate): Indications, Dosing, and Precautions
Augmentin is a broad-spectrum β-lactam/β-lactamase inhibitor combination indicated primarily for skin/soft tissue infections, respiratory tract infections including acute otitis media and sinusitis, and urinary tract infections, with dosing ranging from standard 875/125 mg twice daily in adults to high-dose formulations (90 mg/kg/day divided twice daily in children) for resistant pathogens.
Primary Indications
Pediatric Acute Otitis Media
- AUGMENTIN ES-600 is FDA-approved specifically for recurrent or persistent acute otitis media in children ≥3 months with risk factors: antibiotic exposure within 3 months AND either age ≤2 years or daycare attendance 1
- Targets S. pneumoniae (penicillin MIC ≤2 mcg/mL), β-lactamase-producing H. influenzae, and M. catarrhalis 1
- Not indicated for S. pneumoniae with penicillin MIC ≥4 mcg/mL 1
Skin and Soft Tissue Infections
- For impetigo (Staphylococcus and Streptococcus): 875/125 mg twice daily in adults or 25 mg/kg/day (amoxicillin component) in 2 divided doses in children 2
- Appropriate for methicillin-susceptible S. aureus (MSSA) infections 2
- Not recommended as first-line for MRSA 2
Respiratory Tract Infections
- Community-acquired pneumonia, acute bacterial sinusitis, and acute exacerbations of chronic bronchitis 3, 4
- For acute sinusitis in children: amoxicillin alone is equally effective as amoxicillin-clavulanate with fewer adverse events (gastrointestinal symptoms RR 1.15, yeast infections RR 1.33) 5
- Consider amoxicillin-clavulanate when β-lactamase-producing organisms are suspected 6
Urinary Tract Infections
- Effective for multiply resistant bacteria in UTIs 7
- Standard dose 375 mg three times daily shows ~70% success rate for amoxicillin-resistant organisms 7
Dosing Regimens
Adults
- Standard formulations: 875/125 mg twice daily or 500/125 mg three times daily 1
- High-dose formulation (Augmentin XR): 2000/125 mg twice daily for drug-resistant respiratory pathogens 3
- Administer at the start of meals to minimize gastrointestinal intolerance and enhance clavulanate absorption 1
Pediatric Patients
Standard Dosing:
- 25 mg/kg/day (amoxicillin component) in 2 divided doses for impetigo 2
- 25-50 mg/kg/day in 3-4 divided doses for other infections 2
High-Dose ES-600 Formulation (for resistant AOM):
- 90 mg/kg/day divided every 12 hours for 10 days 1
- Example: 8 kg child receives 3.0 mL twice daily; 40 kg child is the upper weight limit for this formulation 1
- Contains 42.9 mg clavulanic acid per 5 mL (higher than standard suspensions) 1
Critical Caveat: AUGMENTIN ES-600 is NOT interchangeable with other Augmentin suspensions due to different clavulanic acid concentrations 1
Key Precautions and Contraindications
Hepatic Monitoring
- Dose hepatically impaired patients with caution and monitor liver function at regular intervals 1
- Clavulanic acid undergoes primarily hepatic metabolism 6
Gastrointestinal Effects
- Clavulanic acid is strongly associated with diarrhea and C. difficile infection 6
- Twice-daily dosing causes less diarrhea than three-times-daily regimens 8
- The clavulanic acid component limits maximum daily amoxicillin dosing due to tolerability 6
Antimicrobial Stewardship Considerations
- Prefer amoxicillin alone when β-lactamase-producing organisms are not suspected 6, 5
- Amoxicillin-clavulanate is WHO AWaRe "Access" group antibiotic, appropriate for first-line use in targeted infections 4
- For pediatric acute sinusitis, amoxicillin alone is preferred unless treatment failure occurs 5
- Avoid empirical overuse to prevent ESBL selection in Gram-negative pathogens 9
Duration of Therapy
- For protracted bacterial bronchitis in children: 2 weeks is as effective as 4 weeks for clinical cure, though 4 weeks provides longer time to next exacerbation (median 150 vs 36 days) 10
- Standard courses are typically 7-10 days for most infections 1
Resistance Patterns
- Maintains activity against β-lactamase-producing H. influenzae and M. catarrhalis 3
- Low propensity to select resistance mutations 3
- Clavulanic acid has minimal role in respiratory infections beyond β-lactamase inhibition 9
Practical Administration Points
- Reconstituted ES-600 suspension is stable for 10 days under refrigeration 1
- Shake oral suspension well before each use 1
- FLAVORx flavoring (apple, banana cream, bubble gum, cherry, watermelon) may be added immediately after reconstitution 1
- Adults with difficulty swallowing should not receive ES-600 suspension in place of tablets 1