What is the recommended dose of Augmentin (amoxicillin-clavulanate) for a patient with a respiratory infection, considering factors such as age, weight, renal function, and medical history, including allergies to penicillin or other antibiotics?

Augmentin Dosing for Respiratory Tract Infections

For adults with respiratory tract infections, use Augmentin 875 mg/125 mg twice daily for standard cases, or escalate to 2000 mg/125 mg twice daily when antibiotic resistance is likely or for moderate-to-severe infections. 1, 2

Adult Dosing Algorithm

Standard-Dose Regimen (First-Line)

• Augmentin 875 mg/125 mg twice daily is the standard dose for most respiratory tract infections in adults, including sinusitis, community-acquired pneumonia, and acute exacerbations of chronic bronchitis 2, 1
• This regimen is as effective as three-times-daily dosing and causes less diarrhea 3
• Treatment duration is typically 7-10 days for most respiratory infections 1
• For acute bacterial rhinosinusitis specifically, 5-7 days may be sufficient in uncomplicated cases 1

High-Dose Regimen (For Resistant Organisms)

• Augmentin 2000 mg/125 mg twice daily should be used when penicillin-resistant Streptococcus pneumoniae is suspected or confirmed 1, 4
• This high-dose formulation achieves adequate serum concentrations to eradicate strains with amoxicillin MICs up to 4-8 mg/L 1, 4

Risk Factors Requiring High-Dose Therapy

Use the 2000 mg/125 mg twice daily regimen when ANY of these factors are present:

• Recent antibiotic use within the past 4-6 weeks 5, 1
• Age >65 years 1, 6
• Moderate-to-severe infection (frontal or sphenoidal sinusitis, severe pneumonia) 1
• Comorbidities: diabetes mellitus, chronic heart/lung/liver/kidney disease 1, 6
• Immunocompromised status 1, 6
• High community prevalence of penicillin-resistant S. pneumoniae (>10%) 1
• Previous antibiotic treatment failure 1
• Healthcare contact or hospital environment exposure 1

Pediatric Dosing Algorithm

Weight-Based Dosing (Children <40 kg)

For mild disease without recent antibiotic use:

• 25 mg/kg/day divided every 12 hours OR 20 mg/kg/day divided every 8 hours 1, 2

For moderate-to-severe disease or recent antibiotic use:

• High-dose: 90 mg/kg/day of amoxicillin with 6.4 mg/kg/day of clavulanate in two divided doses 5, 1
• This high-dose pediatric formulation is specifically recommended for acute bacterial rhinosinusitis and resistant infections 1

For children ≥40 kg:

• Use adult dosing (875 mg/125 mg twice daily) 2

Neonates and Infants <12 Weeks

• 30 mg/kg/day divided every 12 hours based on the amoxicillin component 2
• Use the 125 mg/5 mL oral suspension formulation 2

Treatment Duration for Children

• 10-14 days for acute bacterial rhinosinusitis (longer than adults) 1, 7
• 7-10 days for other respiratory infections 1
• 10 days for acute otitis media 2

Renal Impairment Adjustments

• GFR <30 mL/min: Do NOT use the 875 mg/125 mg dose 2
• GFR 10-30 mL/min: 500 mg/125 mg or 250 mg/125 mg every 12 hours 2
• GFR <10 mL/min: 500 mg/125 mg or 250 mg/125 mg every 24 hours 2
• Hemodialysis patients: 500 mg/125 mg or 250 mg/125 mg every 24 hours, with an additional dose during and at the end of dialysis 2

Treatment Response Assessment

• Evaluate clinical response within 48-72 hours of initiating therapy 1, 6
• If no improvement or worsening after 72 hours, switch to alternative antimicrobial therapy or reevaluate the diagnosis 1, 6
• Fever should resolve within 24 hours for pneumococcal pneumonia, but may take 2-4 days for other etiologies 5

Penicillin-Allergic Patients

• For non-Type I hypersensitivity (e.g., rash): Consider cephalosporins 5
• For true β-lactam allergy: Use respiratory fluoroquinolones (levofloxacin, moxifloxacin, gatifloxacin) 5, 1
• Alternative options include doxycycline or trimethoprim-sulfamethoxazole, though these have 20-25% bacterial failure rates against major respiratory pathogens 5

Critical Pitfalls to Avoid

• Do NOT substitute two 250 mg/125 mg tablets for one 500 mg/125 mg tablet—they contain different amounts of clavulanic acid and are not equivalent 2
• Do NOT underdose in areas with high penicillin-resistant S. pneumoniae prevalence; always use high-dose formulations (2000 mg/125 mg twice daily for adults or 90 mg/kg/day for children) 1
• Do NOT use 875 mg/125 mg in patients with severe renal impairment (GFR <30 mL/min) 2
• Do NOT use pediatric weight-based formulations in adolescents who can take adult tablets—it's unnecessary and more expensive 7

Specific Infection Considerations

Community-Acquired Pneumonia

• Standard dose: 875 mg/125 mg twice daily for 7-10 days 1
• High-dose regimen if risk factors present 1

Acute Bacterial Rhinosinusitis

• Adults: 875 mg/125 mg twice daily for 5-7 days (or 10-14 days for more severe cases) 1, 7
• Children: 90 mg/kg/day for 10-14 days 5, 1

COPD Exacerbations

• Augmentin is recommended as first-line treatment for moderate-severe exacerbations without Pseudomonas risk factors 1, 6
• Standard adult dosing applies 1