What is the recommended dosage of Augmentin (amoxicillin/clavulanate) for treating a sinus infection?

Augmentin Dosing for Sinus Infection

For adults with acute bacterial sinusitis, the recommended dose is Augmentin 875 mg/125 mg twice daily for 10-14 days. 1, 2, 3

Standard Adult Dosing Algorithm

For mild disease without recent antibiotic use:

• Augmentin 875 mg/125 mg twice daily for 10-14 days is the appropriate regimen 1, 4
• This is the FDA-approved dose for respiratory tract infections including sinusitis 3

For moderate-to-severe disease or recent antibiotic exposure (within 4-6 weeks):

• High-dose Augmentin 2000 mg amoxicillin/125 mg clavulanate twice daily should be used 1, 2
• This higher dose is also indicated in regions with high antibiotic resistance or suspected resistant organisms 1, 2

Treatment Duration and Monitoring

Standard treatment course:

• Continue for 10-14 days 1, 2, 4
• Some guidelines recommend treating until symptom-free for 7 days 2, 4

Assess clinical response at 72 hours (3 days):

• If no improvement or worsening occurs, switch to an alternative antibiotic or reevaluate the diagnosis 1, 2, 4
• If partial improvement is seen, continue the full course 2

Pediatric Dosing Considerations

For children weighing ≥40 kg (approximately 88 lbs):

• Use adult dosing of 875 mg/125 mg twice daily 1, 3
• Treatment duration is 7-10 days for pediatric patients 1

For children <40 kg:

• Weight-based dosing of 45 mg/kg/day divided every 12 hours for more severe infections 3
• 25 mg/kg/day divided every 12 hours for less severe infections 3

Important Clinical Considerations

When to use Augmentin instead of plain amoxicillin:

• Moderate-to-severe illness 2, 4
• Recent antibiotic use within 4-6 weeks 1, 2
• Treatment failure with amoxicillin 2, 4
• High prevalence of β-lactamase-producing H. influenzae in your region 2, 4
• Areas with high antibiotic resistance 1, 2

Critical pitfall to avoid:

• Do NOT substitute two 250 mg/125 mg tablets for one 500 mg/125 mg tablet, as they contain the same amount of clavulanic acid (125 mg) and are not equivalent 3

Penicillin-Allergic Patients

Alternative antibiotics include:

• Doxycycline 1, 2
• Respiratory fluoroquinolones (levofloxacin, moxifloxacin) for severe cases 1, 2
• Note that these alternatives have higher bacteriologic failure rates of 20-25% 4

Evidence Quality Note

Important context on antibiotic use in sinusitis:

• The European Rhinologic Society found no benefit of antibiotics for post-viral acute rhinosinusitis in adults, with more adverse events in the antibiotic group 5
• Antibiotics should only be prescribed for true bacterial sinusitis, not viral upper respiratory infections 2, 4
• High-dose immediate-release formulations showed faster improvement at 3 days compared to standard dosing (52.4% vs 34.4%), though with increased diarrhea risk (15.8% vs 4.8%) 6

Renal Impairment Adjustments

For patients with impaired kidney function:

• GFR <30 mL/min: Do NOT use the 875 mg/125 mg dose 3
• GFR 10-30 mL/min: Use 500 mg/125 mg or 250 mg/125 mg every 12 hours 3
• GFR <10 mL/min: Use 500 mg/125 mg or 250 mg/125 mg every 24 hours 3
• Hemodialysis patients: Give an additional dose during and at the end of dialysis 3