Augmentin Dosing for Acute Bacterial Sinusitis
Recommended Dose
For adults with acute bacterial sinusitis and normal renal function, prescribe amoxicillin-clavulanate 875 mg/125 mg twice daily for 5-10 days. 1, 2, 3
This standard-dose regimen provides 90-92% predicted clinical efficacy against the major pathogens (Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis) and is the preferred first-line antibiotic recommended by the Infectious Diseases Society of America. 1, 2
When to Use High-Dose Augmentin
Escalate to high-dose amoxicillin-clavulanate 2000 mg/125 mg twice daily (not to exceed 2 g amoxicillin every 12 hours) if the patient has: 1, 2, 3
- Recent antibiotic use within the past 4-6 weeks 1
- Age >65 years 1, 2
- Moderate-to-severe symptoms 1, 2
- Comorbid conditions or immunocompromised state 1, 2
- High local prevalence of drug-resistant S. pneumoniae 1
High-dose formulations provide enhanced coverage against resistant organisms, particularly in areas with high prevalence of penicillin-resistant S. pneumoniae. 1
Treatment Duration
Treat for 5-10 days, with most guidelines recommending continuation until symptom-free for 7 days (typically 10-14 days total). 1, 2, 3
Recent evidence supports shorter 5-7 day courses for uncomplicated cases, which demonstrate comparable efficacy to traditional 10-day regimens with fewer adverse effects. 1, 2 However, the standard 10-14 day duration remains widely recommended. 2, 3
Critical Reassessment Timepoints
Reassess at 3-5 days: If no improvement or worsening symptoms, switch to second-line therapy (respiratory fluoroquinolone like levofloxacin 500 mg once daily or moxifloxacin 400 mg once daily). 1, 4, 2
Reassess at 7 days: If symptoms persist, reconfirm the diagnosis, exclude complications, and consider switching antibiotics or obtaining imaging. 1, 4
Waiting beyond 7 days to change therapy in non-responders delays effective treatment and may allow complications to develop. 1, 4
Evidence on High-Dose vs. Standard-Dose
The evidence on high-dose Augmentin is mixed. One randomized trial found that immediate-release high-dose amoxicillin-clavulanate (1750 mg twice daily) led to significantly faster improvement at day 3 compared to standard dose (52.4% vs 34.4%, P=0.04), but this came with increased severe diarrhea (15.8% vs 4.8%). 5 However, a more recent 2021 trial found no benefit of high-dose over standard-dose at day 3 (36.4% vs 44.3%, P=0.35), with similar diarrhea rates. 6
Given this conflicting evidence, reserve high-dose formulations specifically for patients with the risk factors listed above rather than using them routinely. 1, 2
Adjunctive Therapies to Enhance Outcomes
Add intranasal corticosteroids (mometasone, fluticasone, or budesonide twice daily) to all patients—this reduces mucosal inflammation and improves symptom resolution with strong evidence from multiple RCTs. 1, 4, 2
Recommend saline nasal irrigation for symptomatic relief and mucus removal. 1, 4
Prescribe analgesics (acetaminophen or ibuprofen) for pain and fever management. 1, 4
Common Pitfalls to Avoid
Do not prescribe antibiotics for symptoms lasting <10 days unless severe features are present (fever ≥39°C with purulent discharge for ≥3 consecutive days). 1, 4 Most acute rhinosinusitis (98-99.5%) is viral and resolves spontaneously within 7-10 days without antibiotics. 1, 4
Ensure adequate treatment duration—inadequate courses lead to relapse. 2, 3 Complete the full 5-10 day course even after symptoms improve. 4, 2
Gastrointestinal adverse effects are common with amoxicillin-clavulanate, particularly diarrhea (reported in 40-43% of patients, with severe diarrhea in 7-8%). 1 The high-dose formulation may increase this risk. 5, 6
Avoid using first-generation cephalosporins (cephalexin, cefadroxil) as they have inadequate coverage against H. influenzae. 1, 4